Add named taste profiles for per-person recommendations

Named profiles allow each household member to get personalized
recommendations without polluting each other's taste. Includes
profile CRUD API, speaker→profile auto-attribution, recent listen
history endpoint, and profile param on all existing endpoints.
All endpoints backward compatible (no profile param = "default").

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/haunt_fm/api/playlists.py

@@ -19,6 +19,7 @@ class GenerateRequest(BaseModel):
     auto_play: bool = False
     vibe: str | None = None
     alpha: float = Field(default=0.5, ge=0.0, le=1.0)
+    profile: str | None = None
 
 
 @router.post("/generate")
@@ -42,6 +43,7 @@ async def generate(req: GenerateRequest, session: AsyncSession = Depends(get_ses
         vibe_embedding=vibe_embedding,
         alpha=alpha,
         vibe_text=req.vibe,
+        profile_name=req.profile or "default",
     )
 
     # Load playlist tracks with track info