v0.4.0 — chapter outlines for long videos

Long videos get an outline instead of a transcript dump. Chapters come from YouTube or description timestamps. No new runtime dependencies.

New commands and options:

• info VIDEO: metadata and chapters, without the transcript
• search --match phrase: require query words to appear next to each other
• add/get/show JSON includes duration_s and chapters
• list --json includes uploaded_at and ingested_at
• Markdown exports include a chapter table of contents
• Human-mode warning when printing a long transcript without a time window

Existing v0.3 libraries migrate in place (schema 2) and gain chapters from saved descriptions. After migration, v0.3 will refuse the database.

Verified: 61 tests across macOS/Linux and Python 3.9/3.13.

Caption-less videos remain unsupported.