Merge cues at the string level instead of round-tripping through
pycaption, which dropped inline tags and cue settings. STYLE and
REGION blocks are kept, duplicate boundary cues splice correctly,
and a bad timing line now skips the cue instead of crashing.
Also rank pysubs2 above SubtitleEdit for ASS to TTML/VTT since
SubtitleEdit flattens inline styling there. Documented the measured
backend fidelity table and added regression tests for the merge.
Share one best-audio selector across the episode and music paths so best/all works for songs, descriptive audio is capped to one track, and codec_priority is honored. Guard --channels and 16:9 canvas math against tracks missing channel/width metadata. Extend --best-available to video languages and full resolution misses in both normal and hybrid mode, and count only deliverable ranges when reporting missing resolutions. Rank video by resolution before bitrate, and trim group audio selections to one track per song with a warning.
BREAKING CHANGE: a missing resolution with -r HYBRID now errors without --best-available, matching non-hybrid behavior.
Swap cookie/PKCE auth for the OAuth 2.0 device authorization grant with a cached rotating refresh token. Fix the connection-token key (`cat`) and move the cache to {cache}/vpn/ to match ProtonVPN.
BREAKING CHANGE: cookie-file auth removed; run once with `enable: true` to approve a device code.