fix: reconcile missing recurring flow schedules

[chubes4]

Summary

• audit persisted recurring flow definitions against authoritative Action Scheduler coverage and expose a dry-run/apply reconciliation ability plus CLI
• defer activation/deploy repairs until Action Scheduler is ready, lock concurrent repairs, and spread large fleet recovery over 24 hours
• surface missing, invalid, duplicate, and blocked schedule ownership in system health without scheduling around active in-progress work

Testing

• composer lint
• scheduler reconciliation smoke suites
• recurring scheduler idempotency smoke suite
• PHP syntax checks for changed files
• git diff --check
• independent final code review found no blocking correctness issues

Operational Evidence

Production recovery restored 659 recurring Events schedules after 670 flows lost their next run. The initial one-hour repair window would have concentrated 627 starts; this change adds fleet-aware distribution and routine coverage diagnostics so that drift is detected and repaired safely.

Full homeboy review data-machine was not run locally because Homeboy's resource policy rejected the hot 8-CPU host at load 132.2 and no Lab runner was available. Focused Homeboy changed-file lint passed during implementation.

Closes #2902