GitPulse CLI 0.1.6 ships with release automation

This PR marks the 0.1.6 release of the GitPulse CLI. The actual code changes are minimal — version numbers were bumped in three configuration files, and a changelog was generated. The substantive features bundled into this release were implemented across several earlier PRs: end-to-end password protection for published sites, a new link color theme option, pagination for activity feeds, a releases tab, the ability to exclude PRs via a "gitpulse:ignore" label, automatic loading of .env.local for integration tests, AI-generated feature images, and a pluggable image storage layer with Vercel Blob support. Release Please, the automated tool handling this PR, bundles these changes from the manifest and commits them as a coordinated release point.