[Feature] Scalable conversations list with timestamps, filters, and search

[HCH-hash]

Summary

Make the conversations list usable at scale by adding timestamps, filtering (agent / type / status / date), and search.

Problem

The current conversations list shows minimal information and has no filter or search. It works at ~15 conversations but becomes unusable at hundreds. Users cannot quickly find a specific run, agent, or time window.

Proposed Direction

• Show a relative or absolute timestamp on every row.
• Add filters for agent, trigger type, status, and date range.
• Add full-text or title/ID search.
• Optionally support sorting and lightweight pagination or infinite scroll.

Scope

• Product behavior
• Frontend
• API (if list endpoints need richer query parameters)
• Documentation
• Other

Additional Context

• Especially important once teams run many ACP agents in parallel.
• Can start with client-side filtering if the payload stays small, then move filtering server-side as volume grows.

[pullfrog]

  ^{｜ Build this ➔ ｜ Make a plan ➔}