[08abhinav]

Description

Adds the podcast-transcript template (Podcast category). It shows the show name, the episode title, and up to three transcript lines, each with a timestamp (JetBrains Mono), a speaker name in the accent color, and the spoken text.

• A line with blank text is skipped with no gap, even if its time or speaker is filled. With all three blank, the transcript area is hidden.
• A blank time or speaker hides only that part, and the spoken text keeps the same x position on every row (fixed-width columns).
• A long title shrinks with autoFontSize() and then truncates. A long speaker name truncates inside its column. A long line wraps to at most two lines and then truncates.
• Accent and muted colors adjust on light backgrounds, following top-episodes.ts.
• Exported in src/templates/podcast/index.ts and registered at the end of the podcast block in src/templates/registry.ts.

Closes #399
Part of #5

How I Tested This

• Ran npm run dev and rendered /api/og?template=podcast-transcript with the defaults.
• Checked each edge case via the API and the form UI:
  • blank line 2 (row skipped, no gap)
  • blank line with filled time and speaker (still skipped)
  • all three lines blank (transcript area hidden)
  • blank time only, blank speaker only (text stays aligned)
  • very long title, speaker name, and line (shrink, truncate, two-line clamp)
  • light background (#ffffff) with a bright accent (names and timestamps readable)
• Ran npm run check and npm run test

AI Assistance

Claude helped me with debugging the registry issue and a typo in the draft. I reviewed it, ran it locally, and tested all the cases above myself.

Type of Change

• Bug fix
• New template
• New feature
• Documentation
• Tests
• Refactoring
• Performance improvement
• Other (describe below)

Screenshots

1. Default render

2. Blank row skipped

3. Long title, speaker, and line

3. Light background

Checklist

• This PR targets dev
• I was assigned the linked issue
• npm run check passes
• npm run test passes
• For a bug fix: the new test fails without my change
• Tested locally with npm run dev
• Screenshots included for visual changes
• New templates follow the Template Guidelines