Distinguish review threads in the sidebar

[lynnswap]

Purpose

Make repeated review tasks distinguishable in the sidebar without relying on identical first-prompt previews.

Changes

• Show the owned review target, captured branch and short SHA, or chat title as the primary row label.
• Show review lifecycle, source, elapsed or relative time, and a matching state icon as the secondary presentation.
• Associate lifecycle state only with the exact review chat, while preserving useful source labels for ordinary and companion tasks.
• Exercise the production data flow in preview fixtures, including terminal review outcomes and active review sources.
• Load a bounded recency page across all default user-visible Codex thread sources.
• Pin CodexKit to ab025ed970d30c7679913951bdb9fff20a9b77b1.

The CodexKit dependency includes the thread provenance API and composite user-visible source fetching added on main in cc180894, 00a8fe77, and ab025ed9.

Validation

• swift test --build-system swiftbuild --no-parallel
• xcodebuild test -project Tools/ReviewMonitor/CodexReviewMonitor.xcodeproj -scheme CodexReviewMonitor -destination 'platform=macOS,arch=arm64' CODE_SIGNING_ALLOWED=NO CODE_SIGNING_REQUIRED=NO (18 tests)
• Final Codex review: no findings
• Visual preview verification: distinct base branch, uncommitted changes, branch, commit, and custom-target rows rendered with reviewing, cancelled, complete, and failed states
• CodexKit: 405 tests passed, external product consumer built, final Codex review had no findings