feat(sonarr): add season recap downloader

[mvanbaak]

What

New sonarr/connect/download_recap.sh Connect script for Sonarr: downloads the previous season's recap when a new season starts (triggered on the Download event).

Discovery chain

1. TMDB season-videos endpoint (type == "Recap" && official == true) per configured language
2. YouTube official recap search in the series' original language only (iff TMDB found nothing)
3. Optional fan-made recap per FAN_MADE config: never | fallback | always

All candidates are ranked and the single best recap per (season, language) is downloaded. Junk titles (trailers, teasers, soundtracks, reactions, reviews, interviews, single-episode recaps) are filtered. Search width configurable via RECAP_SEARCH_COUNT (default 10).

Storage (Plex extras naming scheme)

STORAGE_MODE config: show (default, Other/), season (Season NN/Other/), or both (show-level download + hardlink into season folder, cp fallback). A recap of season N lands in the Season N+1 folder (the watched season); the filename still names the recapped season. Multi-language support with subtitles for original-language recaps. Bulk mode backfills recaps for all downloaded seasons.

Refactor

• radarr/connect/scripts_common.sh: added sonarr_api_get(), get_series_info(), Sonarr API defaults, and moved shared defaults + lang_to_iso639_1/notify_autopulse from the trailer script (both scripts now source these).
• radarr/connect/download_trailer.sh: dropped duplicated shared code, bumped to 0.4.0. Behavior unchanged.
• New sonarr/connect/scripts.conf.sample, README + AGENTS.md docs.

Notes

• No test suite in this repo; scripts verified via sh -n + shellcheck -e SC1091,SC3043, all clean.
• Uses sonarr_series_tmdbid from the Sonarr API/env directly (no TMDB find call needed).
• Pre-v0.2.0 junk recap files can be cleaned with: find /path/to/Series -path "*/Other/Recap-*" -type f -delete