Add per-episode breakdown to guest-star filmography credits

FilmographyCreditOut already aggregated a guest star's episode
appearances into one row per series with an episode_count, but never
exposed which episodes those were even though the individual episode
Credit rows exist in the database. Adds an `episodes` list (season/
episode number, title, air date, sorted chronologically) alongside the
existing count -- closes a known limitation tracked in docs/api.md.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

app/schemas/person.py

@@ -18,6 +18,14 @@ class PersonSummaryOut(BaseModel):
     popularity: float | None = None
 
 
+class GuestEpisodeOut(BaseModel):
+    id: str
+    season_number: int
+    episode_number: int
+    title: str | None = None
+    air_date: date | None = None
+
+
 class FilmographyCreditOut(BaseModel):
     id: str
     media_id: str
@@ -33,6 +41,10 @@ class FilmographyCreditOut(BaseModel):
     # those are aggregated to one row per series rather than one per
     # episode. None for movie credits and regular (non-guest) series roles.
     episode_count: int | None = None
+    # The individual episodes behind episode_count, sorted by (season,
+    # episode) -- empty for movie credits and regular (non-guest) series
+    # roles, same as episode_count.
+    episodes: list[GuestEpisodeOut] = []
 
 
 class PersonDetailOut(BaseModel):