feat: write all required NFO tags on creation

docs/CHANGELOG.md

@@ -37,6 +37,30 @@ This changelog follows [Keep a Changelog](https://keepachangelog.com/) principle
 
 ---
 
+## [Unreleased] - 2026-02-22
+
+### Added
+
+- **NFO tag completeness (`nfo_mapper.py`)**: All 17 required NFO tags are now
+  explicitly populated during creation: `originaltitle`, `sorttitle`, `year`,
+  `plot`, `outline`, `tagline`, `runtime`, `premiered`, `status`, `imdbid`,
+  `genre`, `studio`, `country`, `actor`, `watched`, `dateadded`, `mpaa`.
+- **`src/core/utils/nfo_mapper.py`**: New module containing
+  `tmdb_to_nfo_model()`, `_extract_rating_by_country()`, and
+  `_extract_fsk_rating()`. Extracted from `NFOService` to keep files under
+  500 lines and isolate pure mapping logic.
+- **US MPAA rating**: `_extract_rating_by_country(ratings, "US")` now maps the
+  US TMDB content rating to the `<mpaa>` NFO tag.
+
+### Changed
+
+- `NFOService._tmdb_to_nfo_model()` and `NFOService._extract_fsk_rating()` moved
+  to `src/core/utils/nfo_mapper.py` as module-level functions
+  `tmdb_to_nfo_model()` and `_extract_fsk_rating()`.
+- `src/core/services/nfo_service.py` reduced from 640 → 471 lines.
+
+---
+
 ## [Unreleased] - 2026-01-18
 
 ### Added