UI cleanup, Devon overhaul, bug fixes, publish ep36

- Fix Devon double messages, add conversation persistence, voice-to-Devon when no caller
- Devon personality: weird/lovable intern on first day, handles name misspellings
- Fix caller gender/avatar mismatch (avatar seed includes gender)
- Reserve Sebastian voice for Silas, ban "eating at me" phrase harder
- Callers now hear Devon's commentary in conversation context
- CSS cleanup: expand compressed blocks, remove inline styles, fix Devon color to warm tawny
- Reaper silence threshold 7s → 6s
- Publish episode 36

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/services/avatars.py

@@ -0,0 +1,83 @@
+"""Avatar service — fetches deterministic face photos from randomuser.me"""
+
+import asyncio
+from pathlib import Path
+
+import httpx
+
+AVATAR_DIR = Path(__file__).parent.parent.parent / "data" / "avatars"
+
+
+class AvatarService:
+    def __init__(self):
+        self._client: httpx.AsyncClient | None = None
+        AVATAR_DIR.mkdir(parents=True, exist_ok=True)
+
+    @property
+    def client(self) -> httpx.AsyncClient:
+        if self._client is None or self._client.is_closed:
+            self._client = httpx.AsyncClient(timeout=10.0)
+        return self._client
+
+    def get_path(self, name: str) -> Path | None:
+        path = AVATAR_DIR / f"{name}.jpg"
+        return path if path.exists() else None
+
+    async def get_or_fetch(self, name: str, gender: str = "male") -> Path:
+        """Get cached avatar or fetch from randomuser.me. Returns file path."""
+        path = AVATAR_DIR / f"{name}.jpg"
+        if path.exists():
+            return path
+
+        try:
+            # Seed includes gender so same name + different gender = different face
+            seed = f"{name.lower().replace(' ', '_')}_{gender.lower()}"
+            g = "female" if gender.lower().startswith("f") else "male"
+            resp = await self.client.get(
+                "https://randomuser.me/api/",
+                params={"gender": g, "seed": seed},
+                timeout=8.0,
+            )
+            resp.raise_for_status()
+            data = resp.json()
+            photo_url = data["results"][0]["picture"]["large"]
+
+            # Download the photo
+            photo_resp = await self.client.get(photo_url, timeout=8.0)
+            photo_resp.raise_for_status()
+
+            path.write_bytes(photo_resp.content)
+            print(f"[Avatar] Fetched avatar for {name} ({g})")
+            return path
+        except Exception as e:
+            print(f"[Avatar] Failed to fetch for {name}: {e}")
+            raise
+
+    async def prefetch_batch(self, callers: list[dict]):
+        """Fetch avatars for multiple callers in parallel.
+        Each dict should have 'name' and 'gender' keys."""
+        tasks = []
+        for caller in callers:
+            name = caller.get("name", "")
+            gender = caller.get("gender", "male")
+            if name and not (AVATAR_DIR / f"{name}.jpg").exists():
+                tasks.append(self.get_or_fetch(name, gender))
+
+        if not tasks:
+            return
+
+        results = await asyncio.gather(*tasks, return_exceptions=True)
+        fetched = sum(1 for r in results if not isinstance(r, Exception))
+        failed = sum(1 for r in results if isinstance(r, Exception))
+        if fetched:
+            print(f"[Avatar] Pre-fetched {fetched} avatars{f', {failed} failed' if failed else ''}")
+
+    async def ensure_devon(self):
+        """Pre-fetch Devon's avatar on startup."""
+        try:
+            await self.get_or_fetch("Devon", "male")
+        except Exception:
+            pass
+
+
+avatar_service = AvatarService()