fix(engine): retain tracked delayed target pins - #7300

All 5 fully-hydrated PRs in this shard were reviewed patch-by-patch and show clean, domain-appropriate Magic: The Gathering engine work (rules fixes, quantity refs, draft collation, integration tests, and visibility hardening). No malicious signals (credential exfiltration, network calls, obfuscation, dependency tampering, CI abuse, permission broadening) were found in any reviewed hunk. The remaining 5 hydrated-but-preview PRs and 23 metadata-only PRs in this shard lack sufficient patch detail for adversarial review. Globally, 70 of 100 candidate PRs were omitted. The high contribution velocity combined with incomplete patch coverage prevents a confident safe or clean overall verdict.