4.1 routing quality + 4.4 persona prompt

- VoiceConfig: add QueryMinScore (default 0.55) + Persona config fields
- voice.go: remove queryMinScore const, wire from cfg.Voice.QueryMinScore
  as reactiveHandler field
- llmphraser.go: add Persona to Config, prepend to system prompts in
  chat and query paths (systemPrompt/querySystemPrompt methods)
- main.go: pass personaFromCfg into both phraser config blocks
- Makefile: add download-embedder target (Xenova/paraphrase-multilingual-
  MiniLM-L12-v2, ~90MB ONNX)
- AGENTS.md: document embedder model download + libonnxruntime setup
- server.go: fix pre-existing wg.Add vs wg.Wait data race using accept
  mutex. make test green, zero races across all 29 packages.

internal/config/config.go

@@ -189,6 +189,18 @@ type VoiceConfig struct {
 	// Default 0.35 if unset.
 	RouterThreshold float64 `json:"router_threshold,omitempty"`
 
+	// QueryMinScore — the note-recall confidence gate. Top cosine below this
+	// ⇒ "I don't know" instead of a guess. Tuned for the ONNX embedder (0.55);
+	// the HashEmbedder floor scores lexically and may never clear it. 0.55
+	// default if unset.
+	QueryMinScore float64 `json:"query_min_score,omitempty"`
+
+	// Persona — optional prompt prefix that tunes maven's character. Prepended
+	// to every LLM system prompt (nudge phrasing, note queries, general
+	// knowledge). Empty string ⇒ current hardcoded persona (feminine-gendered
+	// Russian self-reference). Example: "Be formal and answer in English only."
+	Persona string `json:"persona,omitempty"`
+
 	// Weather — the weather provider config. nil ⇒ the daemon wires
 	// the stub provider (returns ErrNotConfigured — "погода не настроена").
 	// Set provider to "open-meteo" to use the keyless Open-Meteo API.
@@ -309,6 +321,7 @@ const (
 	DefaultRepeatInterval   = 5 * time.Minute
 	DefaultAutotuneInterval = 10 * time.Minute
 	DefaultRouterThreshold  = 0.35
+	DefaultQueryMinScore    = 0.55
 	DefaultToolTimeout      = 30 * time.Second
 )
 
@@ -379,6 +392,9 @@ func (c *Config) applyDefaults() {
 		if c.Voice.RouterThreshold <= 0 {
 			c.Voice.RouterThreshold = DefaultRouterThreshold
 		}
+		if c.Voice.QueryMinScore <= 0 {
+			c.Voice.QueryMinScore = DefaultQueryMinScore
+		}
 		if c.Voice.ToolTimeout <= 0 {
 			c.Voice.ToolTimeout = Duration(DefaultToolTimeout)
 		}

internal/ipc/server.go

@@ -281,9 +281,10 @@ type Server struct {
 	api  atomic.Value // stores CoreAPI
 	path string
 
-	ln   net.Listener
-	wg   sync.WaitGroup
-	done chan struct{}
+	ln     net.Listener
+	wg     sync.WaitGroup
+	done   chan struct{}
+	accept sync.Mutex // guards wg.Add vs Close's wg.Wait sequence
 
 	// Check — optional authorization hook. dispatch runs it BEFORE method
 	// dispatch, with the raw params, so the auth layer can make verdicts
@@ -385,7 +386,12 @@ func (s *Server) Serve() error {
 				return fmt.Errorf("ipc: accept: %w", err)
 			}
 		}
+		// wg.Add under accept mutex so Close's wg.Wait (also under accept) sees
+		// a consistent counter — a connection accepted just before Close closes
+		// the listener must be tracked before Wait starts.
+		s.accept.Lock()
 		s.wg.Add(1)
+		s.accept.Unlock()
 		go func(c net.Conn) {
 			defer s.wg.Done()
 			defer c.Close()
@@ -747,7 +753,14 @@ func (s *Server) Close() error {
 		close(s.done)
 	}
 	err := s.ln.Close()
+	// Under accept lock: after the listener closes, no new Accept can complete,
+	// so no new wg.Add will be called. The Wait is safe to observe the wg
+	// counter because any in-flight Accept that already got a conn either
+	// already called wg.Add (before releasing the lock) or will see the closed
+	// listener error and not call wg.Add at all.
+	s.accept.Lock()
 	s.wg.Wait()
+	s.accept.Unlock()
 	_ = os.Remove(s.path)
 	return err
 }

internal/phraser/llmphraser.go

@@ -37,6 +37,7 @@ type Config struct {
 	NGpuLayers int
 	NCtx       int
 	Timeout    time.Duration
+	Persona    string // optional prompt prefix tuning maven's character
 }
 
 func DefaultConfig(modelPath string) Config {
@@ -185,7 +186,7 @@ func (p *LLMPhraser) PhraseQuery(ctx context.Context, utterance string, notes []
 	if len(notes) == 1 {
 		notes[0] = strings.TrimSpace(notes[0])
 	}
-	sys := "You are maven, a self-hosted personal assistant answering from your notes. Answer briefly and naturally in Russian starting with \"вот что я нашла: \". Respond with just the answer text, no JSON wrapper."
+	sys := p.querySystemPrompt()
 	prompt := fmt.Sprintf(
 		`The user asks: "%s". Your notes matching the query contain: "%s". Answer them naturally and briefly. If the notes don't answer the question, say so.`,
 		utterance, strings.Join(notes, `"; "`),
@@ -248,7 +249,7 @@ type chatResp struct {
 }
 
 func (p *LLMPhraser) chat(ctx context.Context, userPrompt string) (string, error) {
-	return p.chatWithSystem(ctx, systemPrompt(), userPrompt, 256)
+	return p.chatWithSystem(ctx, p.systemPrompt(), userPrompt, 256)
 }
 
 func (p *LLMPhraser) chatWithSystem(ctx context.Context, system, user string, maxTokens int) (string, error) {
@@ -295,8 +296,22 @@ func (p *LLMPhraser) chatWithSystem(ctx context.Context, system, user string, ma
 	return cr.Choices[0].Message.Content, nil
 }
 
-func systemPrompt() string {
-	return `You are maven, a self-hosted personal assistant. Generate brief, natural nudge messages in the user's language (Russian or English). Respond ONLY with valid JSON: {"body": "full voice message", "summary": "brief away-channel version (<60 chars)"}. body is what the user hears on voice; summary is for push notifications (ntfy/telegram) — minimal, no exfil detail.`
+func (p *LLMPhraser) systemPrompt() string {
+	base := `You are maven, a self-hosted personal assistant. Generate brief, natural nudge messages in the user's language (Russian or English). Respond ONLY with valid JSON: {"body": "full voice message", "summary": "brief away-channel version (<60 chars)"}. body is what the user hears on voice; summary is for push notifications (ntfy/telegram) — minimal, no exfil detail.`
+	if p.cfg.Persona != "" {
+		base = p.cfg.Persona + "\n\n" + base
+	}
+	return base
+}
+
+// querySystemPrompt returns the system prompt for PhraseQuery (notes + general
+// knowledge). Prepends the configured persona when set.
+func (p *LLMPhraser) querySystemPrompt() string {
+	base := "You are maven, a self-hosted personal assistant answering from your notes. Answer briefly and naturally in Russian starting with \"вот что я нашла: \". Respond with just the answer text, no JSON wrapper."
+	if p.cfg.Persona != "" {
+		base = p.cfg.Persona + "\n\n" + base
+	}
+	return base
 }
 
 func buildNudgePrompt(c loop.Candidate) string {