fix(vod-script): VOD track dropped when Enhanced Broadcasting is off

[Soulhackzlol]

Problem

A user reported no Twitch VOD audio. With verbose logging on, the script logged VOD track attached, but the post-start check said idx1 present=false ours=false, and the InstantClone trace showed a single audio track from OBS.

Cause

AdvancedOutput::StartStreaming -> SetupVodTrack -> clear_archive_encoder (same in OBS 28 through 32.2) does:

obs_encoder_t *last = obs_output_get_audio_encoder(output, 1); // borrowed, no ref
...
obs_encoder_release(last); // stray release

The script hands its create-ref to the output right away, so the output holds the only reference. The stray release brings that to zero. obs_encoder_destroy then detaches the encoder from the output before obs_output_start.

Enhanced Broadcasting was not affected. It streams through the separate rtmp multitrack video output, and clear_archive_encoder only touches the plain streamOutput. That is why EB + VOD passed the live test.

Fix

• On OBS's plain stream outputs (adv_stream / simple_stream), the script keeps its create-reference for OBS's stray release to consume. The output ends up as the sole owner, and nothing is released after the stream starts, so the earlier crash pattern does not come back.
• Other outputs (EB multitrack) keep the immediate release.
• The post-start check always warns when an attached track has gone missing. It no longer needs verbose mode for that.

Test plan

• Advanced output, EB off: the script log shows no warning, and InstantClone's trace shows two audio tracks to Twitch
• EB on: still works as before
• start / stop / start and close OBS mid-session: no crash
• Twitch VOD has the track-2 audio

[Soulhackzlol]

Superseded: the same fix ships in 0.1.15 as d0a360e on feature/crash-protection (first in v0.1.15-rc.1). It reaches main when 0.1.15 merges.