feat: remove startup NFO repair, update docs and tests

- Remove NFO repair scan step from ARCHITECTURE.md startup sequence
- Update CHANGELOG.md: rephrase perform_nfo_repair_scan as scheduled scan
- Add test verifying perform_nfo_repair_scan is NOT called in lifespan
- Keep existing folder scan wiring tests and unit tests intact
- NFO_GUIDE.md already correctly describes scheduled scan behavior

docs/CHANGELOG.md

@@ -73,17 +73,16 @@ This changelog follows [Keep a Changelog](https://keepachangelog.com/) principle
   that detects incomplete `tvshow.nfo` files and triggers TMDB re-fetch.
   Provides `parse_nfo_tags()`, `find_missing_tags()`, `nfo_needs_repair()`, and
   `NfoRepairService.repair_series()`. 13 required tags are checked.
-- **`perform_nfo_repair_scan()` startup hook
+- **`perform_nfo_repair_scan()`
   (`src/server/services/initialization_service.py`)**: New async function
-  called during application startup. Iterates every series directory, checks
-  whether `tvshow.nfo` is missing required tags using `nfo_needs_repair()`, and
-  either queues the series for background reload (when a `background_loader` is
-  provided) or calls `NfoRepairService.repair_series()` directly. Skips
-  gracefully when `tmdb_api_key` or `anime_directory` is not configured.
-- **NFO repair wired into startup lifespan (`src/server/fastapi_app.py`)**:
-  `perform_nfo_repair_scan(background_loader)` is called at the end of the
-  FastAPI lifespan startup, after `perform_media_scan_if_needed`, ensuring
-  every existing series NFO is checked and repaired on each server start.
+  that iterates every series directory, checks whether `tvshow.nfo` is missing
+  required tags using `nfo_needs_repair()`, and queues the series for background
+  reload via `asyncio.create_task`. Skips gracefully when `tmdb_api_key` or
+  `anime_directory` is not configured.
+- **NFO repair wired into scheduled folder scan (`src/server/services/folder_scan_service.py`)**:
+  `perform_nfo_repair_scan(background_loader=None)` is called during the
+  scheduled daily folder scan, keeping startup fast while ensuring regular
+  maintenance.
 
 ### Changed