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.

cmd/mavend/main.go

@@ -213,6 +213,7 @@ func run(args []string) error {
 				NGpuLayers: cfg.Phraser.NGpuLayers,
 				NCtx:       cfg.Phraser.NCtx,
 				Timeout:    time.Duration(cfg.Phraser.Timeout),
+				Persona:    personaFromCfg(cfg),
 			}
 			if pc.BinPath == "" {
 				pc.BinPath = "llama-server"
@@ -364,6 +365,7 @@ func run(args []string) error {
 					NGpuLayers: cfg.Phraser.NGpuLayers,
 					NCtx:       cfg.Phraser.NCtx,
 					Timeout:    time.Duration(cfg.Phraser.Timeout),
+					Persona:    personaFromCfg(cfg),
 				}
 				if pc.BinPath == "" {
 					pc.BinPath = "llama-server"
@@ -494,3 +496,13 @@ func run(args []string) error {
 	log.Printf("mavend: bye")
 	return nil
 }
+
+// personaFromCfg extracts the voice persona from the config, or returns ""
+// when voice isn't configured. Used to pass a character prompt into the
+// LLM phraser without requiring voice to be enabled.
+func personaFromCfg(cfg *config.Config) string {
+	if cfg.Voice != nil {
+		return cfg.Voice.Persona
+	}
+	return ""
+}

cmd/mavend/voice.go

@@ -228,6 +228,7 @@ func wireVoice(cfg *config.Config, coreAPI ipc.CoreAPI, phr phraser.Phraser, mem
 		weatherLocation:  weatherLocation,
 		memStore:         memStore,
 		dialogueSessions: dialogueSessions,
+		queryMinScore:    cfg.Voice.QueryMinScore,
 	}
 
 	// ----- the server (TCP listener) -----
@@ -261,6 +262,12 @@ type reactiveHandler struct {
 
 	memStore memory.Store
 
+	// queryMinScore — the note-recall confidence gate. Top cosine below this ⇒
+	// "I don't know" instead of a guess. Tuned for the ONNX embedder; a knob, not
+	// load-bearing math (same posture as the presence thresholds). Set by
+	// wireVoice from VoiceConfig; default 0.55.
+	queryMinScore float64
+
 	// dialogueSessions carries slots across turns for follow-ups (single-user
 	// box → one session slot, keyed voiceDialogueID). nil ⇒ no carry-over.
 	dialogueSessions *dialogue.SessionStore
@@ -376,11 +383,6 @@ func (h *reactiveHandler) HandlePushToTalk(ctx context.Context, req voice.PushTo
 // returns a non-empty string when the action path wants to OVERRIDE the
 // reply text (e.g. an action error the user should hear SPECIFICALLY, not
 // a generic "ok"). Errors surface as a short reply text the user hears.
-// queryMinScore — the note-recall confidence gate. Top cosine below this ⇒
-// "no note" instead of a guess. Hand-tuned for the ONNX embedder; a knob, not
-// load-bearing math (same posture as the presence thresholds).
-const queryMinScore = 0.55
-
 func (h *reactiveHandler) applyAction(ctx context.Context, dec router.Decision) string {
 	if dec.Clarify {
 		return "" // the Replier phrases clarify
@@ -541,13 +543,13 @@ func (h *reactiveHandler) applyAction(ctx context.Context, dec router.Decision)
 		// a gap (spec's "not a guesser-of-truth"). Same instinct as the loop's
 		// since(key)==null → don't fire. Tuned for the ONNX embedder; the Hash
 		// floor scores lexically and may rarely clear it.
-		if len(notes) == 0 || notes[0].Score < queryMinScore {
+		if len(notes) == 0 || notes[0].Score < h.queryMinScore {
 			// Long-term memory recall (notes + facts) before general knowledge:
 			// the notes table can't answer fact questions, but the memory store
 			// indexes both. Only runs when notes-RAG already gave up → additive.
 			if h.memStore != nil {
 				if hits, herr := h.memStore.Search(ctx, vec, 3); herr == nil {
-					if text, ok := bestRecall(hits, queryMinScore); ok {
+					if text, ok := bestRecall(hits, h.queryMinScore); ok {
 						return text
 					}
 				}