feat: spirit engine — seance WS, entity minting/Codex, Piper TTS voices, wire telemetry

- WS /ws/session: modes, summon, anomaly fragments, streaming direct contact,
  passive wire-ghost ambient loop, per-user rate limits, event transcript
- entities: anomaly-signature fingerprinting, LLM minting + procedural
  fallback, Codex matching with contact counts and sightings
- tts: 8 local Piper voices (EN/ES), per-entity voice profiles, numpy
  effects chain (pitch/rate/bitcrush/echo/static)
- llm: streaming client, submit_stream in bounded queue, SpiritService
  with offline fallbacks for every channel
- routes: public /api/codex, /api/codex/{id}, /api/stats; /audio static mount
- models: Entity, EntitySighting, Event, ContactSession(entity_id, language)

backend/app/tts/voices.py

@@ -0,0 +1,40 @@
+"""Catalog of locally installed Piper voices.
+
+Each entity's voice_profile pins one of these voice ids plus pitch/rate/noise
+shaping, giving every spirit its own recognizable throat."""
+
+from dataclasses import dataclass
+
+
+@dataclass(frozen=True)
+class Voice:
+    id: str
+    model_file: str
+    language: str
+    description: str
+
+
+VOICES: dict[str, Voice] = {
+    "lessac": Voice("lessac", "en_US-lessac-low.onnx", "en", "a measured American woman"),
+    "amy": Voice("amy", "en_US-amy-low.onnx", "en", "a soft American woman"),
+    "ryan": Voice("ryan", "en_US-ryan-low.onnx", "en", "a deep American man"),
+    "alan": Voice("alan", "en_GB-alan-low.onnx", "en", "a low British man"),
+    "hfc_male": Voice("hfc_male", "en_US-hfc_male-medium.onnx", "en", "a worn male voice"),
+    "hfc_female": Voice(
+        "hfc_female", "en_US-hfc_female-medium.onnx", "en", "a worn female voice"
+    ),
+    "davefx": Voice("davefx", "es_ES-davefx-medium.onnx", "es", "una voz masculina grave"),
+    "ald": Voice("ald", "es_MX-ald-medium.onnx", "es", "una voz masculina seca"),
+}
+
+EN_VOICE_IDS = [v.id for v in VOICES.values() if v.language == "en"]
+ES_VOICE_IDS = [v.id for v in VOICES.values() if v.language == "es"]
+
+
+def pick_voice(voice_id: str | None, language: str) -> Voice:
+    """Resolve an entity's voice id, falling back to a language-appropriate default."""
+    if voice_id and voice_id in VOICES:
+        voice = VOICES[voice_id]
+        if voice.language == language:
+            return voice
+    return VOICES["davefx" if language == "es" else "lessac"]