ci: bootstrap FR-flow callers on main

[LukasWodka]

Bootstrap commit: copies the FR-flow callers onto the protected branch so the FR gate activates on PRs targeting it.

After this lands, opening any PR to this branch will trigger fr-gate-caller.yml, which checks that contained items are in Ready for prod (or Ready for staging for staging-target PRs).

🤖 Generated with Claude Code

[LukasWodka]

@saadqbal could you give this a quick approve when you get a chance? Mechanical bootstrap — just copies two thin caller workflows from develop onto this branch so the new FR-gate / /fr-pass flow activates on PRs targeting it. All real logic lives in tracebloc/.github; these are 5-line subscription files.

Once all 7 of these are merged across the active repos, I can wire fr-gate up as a required status check on staging/main/master. Until then it runs as informational only.

Context: tracebloc/.github#39 (now on main) — closes the Done→Prod mismatch that was breaking closure-router for ~24h.