Add WebCodecs Bug

Workflow

1. Read packages/docs/docs/mediabunny/webcodecs-bugs.mdx to understand the current table format.
2. Open the provided issue URL with the browser:control-in-app-browser skill.
3. On the issue page, verify:
   • issue title
   • created or filed date
   • reporter or filed-by identity
   • current status and resolution state
4. Map the browser tracker to the table fields:
   • Product: Chromium issues are Chrome, WebKit Bugzilla issues are Safari, Mozilla Bugzilla issues are Firefox.
   • Filed by: use the known handle from the task when the tracker only exposes a redacted email. Known reporter mappings:
     • musica-viva.de or dp@...@musica-viva.de → @Vanilagy
   • Fixed?: use Yes only for fixed or verified-fixed issues, No for open/new/assigned/unresolved issues, and Won't fix for explicitly rejected or wontfix resolutions.
5. Add one Markdown table row to packages/docs/docs/mediabunny/webcodecs-bugs.mdx.

Preserve the existing table columns and wording. Do not add a date column unless the docs file already has one or the user explicitly asks for it.

Verification

After editing, inspect the diff and confirm the row has the right URL, product, filed-by value, and fixed state.