Add plugin entry: recent-archives

[braedonsaunders]

What the plugin does

Adds a per-project Recently archived filter to the sidebar Display options menu (next to Organize / Sort by). Turning it on shows the project's newest archived threads as a dimmed section at the bottom of that project's thread list. Clicking a row previews the thread without restoring it; Unarchive is available on the row (hover), in the archived-thread banner, and in the thread header. A "Show all N more" control expands past the newest few. Also registers a bb recent-archives CLI command (list/unarchive).

Source release

• Repository: https://github.com/braedonsaunders/bb-plugin-recent-archives
• Tag: v0.1.0 (annotated), range ^0.1.0

Plugin checks

• npm test — 7/7 unit tests pass
• tsc --noEmit — clean
• bb plugin build — builds dist/app.js, dist/app.css, dist/app.meta.json
• Installed and exercised end to end against a live BB (menu toggle, per-project section, preview, unarchive)

Marketplace checks

• npm run build — succeeds, 90 entries
• npm run check — my entry's release tag is publicly visible (git ls-remote --tags shows v0.1.0); the run reports a pre-existing failure for the unrelated ports entry whose source repository no longer exists

Security notes

• Frontend uses content scripts to inject the menu item and sidebar section into the BB app DOM; no external network calls
• Backend uses only the BB SDK thread APIs (list, get, open, unarchive) plus plugin settings and realtime