chore: release opencode-drive 1.2.0

[kitlangton]

What

Release opencode-drive@1.2.0 with run- and restart-generation-scoped media outputs from #36.

How

• Consume .changeset/run-scoped-media.md.
• Bump the package and workspace lockfile from 1.1.0 to 1.2.0.
• Add the generated changelog entry.

Testing

• bun run release:validate
• 158 Effect tests passed.
• 52 CLI integration tests passed.
• Packed artifact contains 94 expected files.
• Installed opencode-drive-1.2.0.tgz in a clean consumer.
• Loaded every public entry point and typechecked runtime controls for shell, webfetch, and websearch.