Ship voice enrolment, and report recognition as blocked (#255)

Maven can now be told who someone is. She cannot yet tell who is speaking,
and this commit is careful to say so rather than pretend otherwise.

What works: profiles are enrolled from several deliberately recorded samples,
listed, and deleted. They live in the existing memory_vectors table under a
"speaker:" id prefix, so there is no migration; what that needed was a wider
interface than memory.Store, hence memory.Catalog with ByPrefix and Delete.
Delete is the load-bearing half — a voiceprint someone asked to be rid of has
to actually go, and a search-only store cannot do that. InMemoryStore.Insert
became an upsert by id to match what the persistent store already did.

What does not work, and why it is not faked: there is no speaker-embedding
model on this box. Sixteen ggufs in /mnt/hdd1/llms, all text; no ECAPA, no
x-vector, no titanet, no wespeaker, no .onnx anywhere under /mnt/hdd1. So
newSpeakerEmbedder returns nil, internal/speaker falls back to
speaker.Disabled, Identify answers ErrDisabled, and the daemon logs which
half is off at startup. The plan's "simple MFCC + GMM" floor is refused in
the package comment: MFCC cosine distance detects channel and loudness as
much as voice, and a biometric that is confidently wrong writes false claims
about named people into his memory. A bad floor is worse than none here.

Refused as well, and the reason is in enroll.go's doc comment: the plan asked
for unknown speakers to be enrolled on first interaction with a TTS "кто
это?". There is no request shape in the protocol that could express that.
Taking a biometric of whoever walks past the microphone does it to guests who
are not party to the exchange, and a synthesised question into a room is not
consent from whoever answers.

Authority: enrolment is AuthStepUp, because it is a deliberate sit-down act
that writes a biometric of a named person and never something done by voice
mid-conversation. Deletion is one rung lower at AuthWrite, deliberately
inverting the usual pattern — getting rid of a biometric must never be the
harder half. Listing is AuthRead and never returns the vectors themselves.

Off unless configured: no speaker block means the three methods answer
ErrUnknownMethod, so a default box has no wire path that takes a voiceprint.

make build and make test pass.

Vikunja #255

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TrVSBKe3RFDF4fGYKWYQnX

internal/ipc/api.go

@@ -301,6 +301,51 @@ type CaptureStatusResp struct {
 	Bytes   int       `json:"bytes,omitempty"`
 }
 
+// EnrollSpeakerReq — register a voice (Vikunja #255).
+//
+// Samples are separate utterances recorded deliberately for this purpose, not
+// audio harvested from ordinary turns. internal/speaker requires several of
+// them totalling enough seconds, and refuses one long clip: a profile built
+// from a single sentence encodes that sentence as much as the person.
+//
+// There is no "enrol whoever just spoke" request shape, and that omission is
+// the point. Taking a biometric of a guest because they walked past the
+// microphone is not something a wire protocol should make easy.
+type EnrollSpeakerReq struct {
+	ID      string        `json:"id"`
+	Name    string        `json:"name,omitempty"`
+	Samples []audio.Audio `json:"samples"`
+}
+
+// Speaker — one enrolled voice as a surface sees it. The voiceprint itself is
+// never sent: a listing says who is enrolled, it does not hand out the
+// biometric.
+type Speaker struct {
+	ID       string    `json:"id"`
+	Name     string    `json:"name"`
+	Enrolled time.Time `json:"enrolled"`
+	Samples  int       `json:"samples"`
+}
+
+// EnrollSpeakerResp — the profile that was written.
+type EnrollSpeakerResp struct {
+	Speaker Speaker `json:"speaker"`
+}
+
+// ListSpeakersResp — who is enrolled, sorted by id. Enabled is false when no
+// embedding model is wired, which is this box's state: the profiles can be
+// listed and deleted, nothing can be recognised.
+type ListSpeakersResp struct {
+	Speakers []Speaker `json:"speakers"`
+	Enabled  bool      `json:"enabled"`
+}
+
+// ForgetSpeakerReq — delete one voiceprint. This is the request that must
+// always work; a biometric someone asked to be rid of has to actually go.
+type ForgetSpeakerReq struct {
+	ID string `json:"id"`
+}
+
 // SwapModelReq — load another resident model without restarting the daemon
 // (Vikunja #250). ModelPath must be one of the paths in phraser.swap_models;
 // anything else is ErrForbidden, and an unconfigured allowlist makes the whole

internal/ipc/client.go

@@ -515,6 +515,34 @@ func (c *Client) CaptureStatus(ctx context.Context) (CaptureStatusResp, error) {
 	return r, nil
 }
 
+// EnrollSpeaker registers a voice from several deliberately recorded samples
+// (Vikunja #255). ErrUnknownMethod means no speaker block is configured, which
+// is the default: on an unconfigured box there is no way to take a voiceprint.
+func (c *Client) EnrollSpeaker(ctx context.Context, req EnrollSpeakerReq) (EnrollSpeakerResp, error) {
+	var r EnrollSpeakerResp
+	if err := c.call(ctx, MethodEnrollSpeaker, req, &r); err != nil {
+		return EnrollSpeakerResp{}, err
+	}
+	return r, nil
+}
+
+// ListSpeakers reports who is enrolled. The voiceprints themselves stay in
+// core. Enabled is false when profiles exist but no embedding model is wired,
+// so a surface can say "enrolled, not recognising" rather than implying Maven
+// knows who is talking.
+func (c *Client) ListSpeakers(ctx context.Context) (ListSpeakersResp, error) {
+	var r ListSpeakersResp
+	if err := c.call(ctx, MethodListSpeakers, nil, &r); err != nil {
+		return ListSpeakersResp{}, err
+	}
+	return r, nil
+}
+
+// ForgetSpeaker deletes one voiceprint.
+func (c *Client) ForgetSpeaker(ctx context.Context, id string) error {
+	return c.call(ctx, MethodForgetSpeaker, ForgetSpeakerReq{ID: id}, nil)
+}
+
 // SwapModel asks core to load another resident model (Vikunja #250).
 // ErrUnknownMethod means core has no phraser.swap_models allowlist configured;
 // ErrForbidden means the path is not on it, or step-up was not asserted. A

internal/ipc/server.go

@@ -473,6 +473,13 @@ type Server struct {
 	CaptureStopFn   CaptureStopFunc
 	CaptureStatusFn CaptureStatusFunc
 
+	// Speaker* — voice identification (Vikunja #255). Set by the daemon only
+	// when a speaker block is configured; nil ⇒ all three methods answer
+	// ErrUnknownMethod, so on an unconfigured box no wire path enrols a voice.
+	EnrollSpeakerFn EnrollSpeakerFunc
+	ListSpeakersFn  ListSpeakersFunc
+	ForgetSpeakerFn ForgetSpeakerFunc
+
 	// UnlockFn — unwraps the store encryption key from the wrapped blob using
 	// the passkey credential public key, opens the encrypted store, and wires
 	// the rest of the daemon (voice, loop, delivery). Set by the daemon when
@@ -510,6 +517,12 @@ type CaptureAppendFunc func(ctx context.Context, req CaptureAppendReq) (CaptureA
 type CaptureStopFunc func(ctx context.Context, req CaptureStopReq) (CaptureStopResp, error)
 type CaptureStatusFunc func(ctx context.Context) (CaptureStatusResp, error)
 
+// EnrollSpeakerFunc / ListSpeakersFunc / ForgetSpeakerFunc — the core-side
+// halves of voice enrolment.
+type EnrollSpeakerFunc func(ctx context.Context, req EnrollSpeakerReq) (EnrollSpeakerResp, error)
+type ListSpeakersFunc func(ctx context.Context) (ListSpeakersResp, error)
+type ForgetSpeakerFunc func(ctx context.Context, req ForgetSpeakerReq) error
+
 // CheckFunc — the auth hook signature. Wired by the daemon (auth.Gate.Check
 // satisfies this); dispatch calls it once per request after param-unmarshal
 // independence (it gets the raw params, may unmarshal what it needs — ipc
@@ -1024,6 +1037,43 @@ func (s *Server) dispatch(ctx context.Context, req Request) (json.RawMessage, er
 		}
 		return nil, fmt.Errorf("%w: %s", ErrUnknownMethod, req.Method)
 
+	case MethodEnrollSpeaker:
+		if s.EnrollSpeakerFn != nil {
+			var p EnrollSpeakerReq
+			if err := unmarshalParams(req.Params, &p); err != nil {
+				return nil, err
+			}
+			resp, err := s.EnrollSpeakerFn(ctx, p)
+			if err != nil {
+				return nil, err
+			}
+			return marshalResult(resp), nil
+		}
+		return nil, fmt.Errorf("%w: %s", ErrUnknownMethod, req.Method)
+
+	case MethodListSpeakers:
+		if s.ListSpeakersFn != nil {
+			resp, err := s.ListSpeakersFn(ctx)
+			if err != nil {
+				return nil, err
+			}
+			return marshalResult(resp), nil
+		}
+		return nil, fmt.Errorf("%w: %s", ErrUnknownMethod, req.Method)
+
+	case MethodForgetSpeaker:
+		if s.ForgetSpeakerFn != nil {
+			var p ForgetSpeakerReq
+			if err := unmarshalParams(req.Params, &p); err != nil {
+				return nil, err
+			}
+			if err := s.ForgetSpeakerFn(ctx, p); err != nil {
+				return nil, err
+			}
+			return marshalResult(nil), nil
+		}
+		return nil, fmt.Errorf("%w: %s", ErrUnknownMethod, req.Method)
+
 	case MethodModelStatus:
 		if s.ModelStatusFn != nil {
 			resp, err := s.ModelStatusFn(ctx)

internal/ipc/speaker_test.go

@@ -0,0 +1,123 @@
+package ipc
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/kami/maven/internal/audio"
+)
+
+// The default that matters most for a biometric: on a core that was never
+// configured with a speaker block, there is no wire path that takes a
+// voiceprint, and none that lists the ones that might exist.
+func TestSpeaker_OffUnlessConfigured(t *testing.T) {
+	_, _, cli, _ := newServerWithStore(t)
+	ctx := context.Background()
+
+	if _, err := cli.EnrollSpeaker(ctx, EnrollSpeakerReq{ID: "kami"}); !errors.Is(err, ErrUnknownMethod) {
+		t.Errorf("EnrollSpeaker error = %v, want ErrUnknownMethod", err)
+	}
+	if _, err := cli.ListSpeakers(ctx); !errors.Is(err, ErrUnknownMethod) {
+		t.Errorf("ListSpeakers error = %v, want ErrUnknownMethod", err)
+	}
+	if err := cli.ForgetSpeaker(ctx, "kami"); !errors.Is(err, ErrUnknownMethod) {
+		t.Errorf("ForgetSpeaker error = %v, want ErrUnknownMethod", err)
+	}
+}
+
+// Enrolment carries several samples across the boundary byte for byte — a
+// profile averaged over the wrong bytes is a profile of nobody.
+func TestSpeaker_EnrollCrossesTheWire(t *testing.T) {
+	_, srv, cli, _ := newServerWithStore(t)
+	ctx := context.Background()
+
+	enrolled := time.Now().UTC().Truncate(time.Second)
+	var gotID, gotName string
+	var gotSamples [][]byte
+
+	srv.EnrollSpeakerFn = func(_ context.Context, req EnrollSpeakerReq) (EnrollSpeakerResp, error) {
+		gotID, gotName = req.ID, req.Name
+		for _, s := range req.Samples {
+			gotSamples = append(gotSamples, s.Bytes)
+		}
+		return EnrollSpeakerResp{Speaker: Speaker{
+			ID: req.ID, Name: req.Name, Enrolled: enrolled, Samples: len(req.Samples),
+		}}, nil
+	}
+
+	mk := func(b byte, n int) audio.Audio {
+		buf := make([]byte, n)
+		for i := range buf {
+			buf[i] = b
+		}
+		return audio.Audio{Format: audio.PCM16kMono, Bytes: buf}
+	}
+	samples := []audio.Audio{mk(1, 64), mk(2, 96), mk(3, 128)}
+
+	resp, err := cli.EnrollSpeaker(ctx, EnrollSpeakerReq{ID: "kami", Name: "Ками", Samples: samples})
+	if err != nil {
+		t.Fatalf("EnrollSpeaker: %v", err)
+	}
+	if gotID != "kami" || gotName != "Ками" {
+		t.Errorf("server saw id=%q name=%q", gotID, gotName)
+	}
+	if len(gotSamples) != 3 {
+		t.Fatalf("server saw %d samples, want 3", len(gotSamples))
+	}
+	for i, want := range samples {
+		if string(gotSamples[i]) != string(want.Bytes) {
+			t.Errorf("sample %d altered in transit", i)
+		}
+	}
+	if resp.Speaker.Samples != 3 || !resp.Speaker.Enrolled.Equal(enrolled) {
+		t.Errorf("profile came back wrong: %+v", resp.Speaker)
+	}
+}
+
+// A listing says who is enrolled and whether recognition actually works. On
+// this box the honest answer is "enrolled, not recognising", and the response
+// has to be able to say so — otherwise a surface implies Maven knows who is
+// talking when nothing on disk can tell.
+func TestSpeaker_ListReportsDisabledRecognition(t *testing.T) {
+	_, srv, cli, _ := newServerWithStore(t)
+	ctx := context.Background()
+
+	srv.ListSpeakersFn = func(context.Context) (ListSpeakersResp, error) {
+		return ListSpeakersResp{
+			Speakers: []Speaker{{ID: "kami", Name: "Ками", Samples: 3}},
+			Enabled:  false,
+		}, nil
+	}
+
+	resp, err := cli.ListSpeakers(ctx)
+	if err != nil {
+		t.Fatalf("ListSpeakers: %v", err)
+	}
+	if len(resp.Speakers) != 1 || resp.Speakers[0].ID != "kami" {
+		t.Fatalf("speakers = %+v", resp.Speakers)
+	}
+	if resp.Enabled {
+		t.Error("Enabled = true; the seam must be able to report that nothing recognises")
+	}
+}
+
+// Deletion reaches core with the id intact and reports success. This is the
+// request that must always work.
+func TestSpeaker_ForgetReachesCore(t *testing.T) {
+	_, srv, cli, _ := newServerWithStore(t)
+	ctx := context.Background()
+
+	var forgot string
+	srv.ForgetSpeakerFn = func(_ context.Context, req ForgetSpeakerReq) error {
+		forgot = req.ID
+		return nil
+	}
+	if err := cli.ForgetSpeaker(ctx, "гость"); err != nil {
+		t.Fatalf("ForgetSpeaker: %v", err)
+	}
+	if forgot != "гость" {
+		t.Errorf("core forgot %q, want %q", forgot, "гость")
+	}
+}

internal/ipc/wire.go

@@ -59,6 +59,9 @@ const (
 	MethodCaptureAppend          Method = "capture_append"
 	MethodCaptureStop            Method = "capture_stop"
 	MethodCaptureStatus          Method = "capture_status"
+	MethodEnrollSpeaker          Method = "enroll_speaker"
+	MethodListSpeakers           Method = "list_speakers"
+	MethodForgetSpeaker          Method = "forget_speaker"
 )
 
 // Request — one frame from module to core. Params is the JSON-encoded argument