Offload /api/v1/videos page read off the event loop

[groupthinking]

Move the blocking video list count+page filesystem work for GET /api/v1/videos onto a worker thread without changing the response contract.

[linear-code]

GRV-320

[github-actions]

👋 Thanks for opening this issue! It has been automatically labeled for triage.

[coderabbitai]

⚠️ Possible Duplicate Issue(s)

• perf: /api/v1/videos blocks the event loop on uncached per-page filesystem reads #1379

🔗 Related PRs

#1288 - perf: scan processed-video cache off the event loop [merged]
#1304 - perf: offload video-detail cache read, drop the stat probe [merged]

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