feat: improve workflow detail pager

[yycholla]

Summary

• show a compact agent-detail summary by default: completed agents show their final result, while active/failed agents show their prompt and two latest history events
• retain full agent results and expose an explicit full pager with Markdown/code highlighting, line/page/end navigation, live tail mode, and bounded short-terminal rendering
• keep long run lists focused on the selected item, coalesce relevant agentHistory refreshes, cache expensive rendering/run reads, and document the new navigator controls

Details

The full pager can be opened from any agent detail with Enter/Right. It supports:

• j/k or arrow keys for line scrolling
• PgUp/PgDn (plus common control-key aliases) for page scrolling
• g/G or Home/End for boundary jumps
• t for live tail/follow mode
• Enter or Esc to return to the compact summary

Markdown results use Pi's Markdown renderer. Structured results are rendered as highlighted JSON, saved workflow scripts as JavaScript, raw read history inherits syntax highlighting from the requested file path, and write calls render their target path and source directly instead of dumping a raw JSON argument envelope.

To keep large run histories responsive, each navigator frame shares one persisted snapshot, persistence briefly caches repeated list reads, Markdown/highlighting output is cached per overlay, and history redraws are limited to the selected agent. Terminal runs also store each full agent result only once instead of duplicating it in both the agent snapshot and resume journal.

Testing

• npm test — 942 tests passed
• added coverage for compact completed/running/error summaries, de-duplicated full-result persistence, per-frame/list caching, pager toggling and back behavior, line/page/end key mappings, tail following, raw-read and write-source syntax highlighting, short viewports, and long run lists
• manually exercised with real Pi subagent workflows that performed multiple source reads and wrote/read substantial temporary TypeScript fixtures

Compatibility

• no new configuration or workflow tool parameters
• WorkflowAgentSnapshot.result is optional
• existing saved runs continue to render through resultPreview when no full result is available

[QuintinShaw]

Really nice work — the pager, the syntax highlighting, and the caching (bounded LRU, content-keyed) are all clean, and the 923-test suite is green.

One blocking issue before merge, in the result-dedup change. persistRun now strips agents[].result for any non-terminal run (keepsResumeJournal is true for running/paused/failed), leaving the full value only in the journal. But persistedToSnapshot — the cold-read path used whenever getRun() misses, i.e. after a pi restart or from another session — only reads agents[].result/resultPreview and never consults p.journal. So once you restart pi and open /workflows on a previously failed/paused/interrupted run, its completed agents show only the truncated preview, even though the full result is still on disk in the journal. It's not a crash and the bytes aren't lost, but it's a durability/UX regression vs main (which persisted the full result into agents[]) and it undercuts exactly the after-the-fact inspection the pager is for. Same-session live views are unaffected.

Suggested fix: in persistedToSnapshot, when a done agent has no result, reconstruct it from p.journal by positional call index (journal .index is the call index — the same match resume() already relies on). A regression test that persists a non-terminal run, re-reads it via a fresh manager, and asserts the pager sees the full result would lock it in — the current tests only exercise completed/live paths.

Two minor, optional: Right on an already-open pager toggles it closed (the description frames Right as "open"); and the shared historyRenderTimer can drop a coalesced history update when you switch agents mid-window (self-heals on the next event). It also needs a quick rebase onto current main (disjoint files, should be clean).

Happy to take the journal-fallback fix myself and push to your branch if you'd prefer — your call.

[yycholla]

@QuintinShaw Fix is in

• Right input now only opens the pager; Enter still toggles it.
• History redraw tracks the latest active agent, preventing dropped updates after switching agents.