Entry, Manifest, VaultConfig types mirroring the Rust data model, plus
a discriminated-union Request type for all popup/content-to-service-worker messages.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Manifest, package.json, tsconfig, webpack config, popup HTML shell,
WASM type declarations, and .gitignore entries for the Chrome MV3 extension.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>