security: harden Time for a public repo (#45)

- beats_of/verdict/retry: trust only github-actions[bot] and owner/member/collaborator authors (forged state and stranger retries on a public repo)
- touches_protected: paginate pull files and include previous_filename
- browser_check: drop .git after clone, serve only the venture folder, Chrome with no network but localhost
- Hands.run: execute in a docker container when a daemon exists (TIME_RUN_IMAGE), host shell fallback
- tests: logins on fake comments, stranger retry/forged beat cases, paginated files fake


Claude-Session: https://claude.ai/code/session_01CYHXFvWMCs1GUmRmpySqQ6

Co-authored-by: claude <noreply@anthropic.com>

.github/workflows/heartbeat.yml

@@ -40,6 +40,7 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           CURSOR_API_KEY: ${{ secrets.CURSOR_API_KEY }}
           VENICE_API_KEY: ${{ secrets.VENICE_API_KEY }}
+          TIME_RUN_IMAGE: node:22-bookworm   # the worker's shell runs in a throwaway container, not next to these secrets
           TIME_MODE: ${{ vars.TIME_MODE }}
           TIME_DAILY_CAP: ${{ vars.TIME_DAILY_CAP }}
           TIME_CURSOR_MODEL: ${{ vars.TIME_CURSOR_MODEL }}

.github/workflows/venture.yml

@@ -38,6 +38,7 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           VENICE_API_KEY: ${{ secrets.VENICE_API_KEY }}
+          TIME_RUN_IMAGE: node:22-bookworm   # the worker's shell runs in a throwaway container, not next to these secrets
           CLOUDFLARE_API_TOKEN: ${{ secrets.CLOUDFLARE_API_TOKEN }}     # optional: a backend per venture (cloudflare.py)
           CLOUDFLARE_ACCOUNT_ID: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
           TIME_VENTURE_DOMAIN: ${{ vars.TIME_VENTURE_DOMAIN }}