feat: US-003 - Creează catalogul de voci tts_voices.json cu seed inițial

- tts_voices.json (nou): seed 17 intrări — M1-M5/F1-F5 supertonic, Marius 1-3
  și Paula 1-3 pockettts (state_path spre models/voices/*.safetensors), alba
  pockettts (voice_url)
- .gitignore: +*.lock pentru sidecar-uri jsonlock
- elimină approved-tasks.json.lock din git (sidecar gol, jsonlock îl recreează)
- scris prin src/jsonlock.py write_locked()
- gates: /review (backend) PASS, db (schema manuală) PASS, pytest 1043 passed
  (22 eșecuri preexistente neschimbate)

tools/pocket_tts_add_voice.py

@@ -0,0 +1,98 @@
+#!/usr/bin/env python3
+"""Export a pocket-tts voice state from a WAV sample into tts_voices.json.
+
+Must run with <.venv-pockettts>/bin/python (torch + pocket-tts installed
+there), never with the main .venv:
+
+    .venv-pockettts/bin/python tools/pocket_tts_add_voice.py \\
+        --wav /path/to/sample.wav --name "Marius"
+
+Determines the next free index for --name by scanning tts_voices.json (an
+entry counts as free if it's absent, or present but its state_path file
+doesn't exist yet on disk), exports the voice state to
+models/voices/<slug>.safetensors, and registers it in tts_voices.json via
+src.jsonlock.
+"""
+import argparse
+import re
+import sys
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).resolve().parent.parent
+CATALOG_PATH = REPO_ROOT / "tts_voices.json"
+VOICES_DIR = REPO_ROOT / "models" / "voices"
+
+sys.path.insert(0, str(REPO_ROOT))
+
+from src.credential_store import get_secret  # noqa: E402
+from src.jsonlock import read_locked, write_locked  # noqa: E402
+
+
+def _slugify(name: str) -> str:
+    return re.sub(r"[^a-z0-9]+", "-", name.lower()).strip("-")
+
+
+def _next_free_index(catalog: dict, name: str) -> int:
+    n = 1
+    while True:
+        entry = catalog.get(f"{name} {n}")
+        if entry is None:
+            return n
+        state_path = entry.get("state_path")
+        if state_path and not (REPO_ROOT / state_path).exists():
+            return n
+        n += 1
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--wav", required=True, help="Path to source WAV sample")
+    parser.add_argument("--name", required=True, help="Base voice name, e.g. 'Marius'")
+    args = parser.parse_args()
+
+    wav_path = Path(args.wav).expanduser().resolve()
+    if not wav_path.exists():
+        print(f"[pocket_tts_add_voice] ERROR: wav not found: {wav_path}", file=sys.stderr)
+        return 1
+
+    import os
+
+    hf_token = get_secret("hf_token")
+    if not hf_token:
+        print(
+            "[pocket_tts_add_voice] ERROR: hf_token lipsește din keyring (service echo-core).",
+            file=sys.stderr,
+        )
+        return 1
+    os.environ["HF_TOKEN"] = hf_token
+
+    from pocket_tts import TTSModel, export_model_state
+
+    catalog = read_locked(str(CATALOG_PATH))
+    index = _next_free_index(catalog, args.name)
+    full_name = f"{args.name} {index}"
+    slug = _slugify(full_name)
+    VOICES_DIR.mkdir(parents=True, exist_ok=True)
+    export_path = VOICES_DIR / f"{slug}.safetensors"
+
+    print("[pocket_tts_add_voice] Loading pocket-tts model...")
+    model = TTSModel.load_model()
+    print(f"[pocket_tts_add_voice] Exporting voice state from {wav_path} -> {export_path}")
+    state = model.get_state_for_audio_prompt(audio_conditioning=str(wav_path), truncate=True)
+    export_model_state(state, str(export_path))
+
+    def _register(data: dict) -> dict:
+        data[full_name] = {
+            "engine": "pockettts",
+            "state_path": f"models/voices/{slug}.safetensors",
+            "owner": args.name,
+        }
+        return data
+
+    write_locked(str(CATALOG_PATH), _register)
+    print(f"[pocket_tts_add_voice] Registered voice '{full_name}' -> {export_path}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())