feat: direct acpmux React agent pane

[teamleaderleo]

This PR carries the React TypeScript agent pane over a direct authenticated acpmux WebSocket client. Swift hosts WKWebView and provides the endpoint, token, and initial session. React attaches, folds the versioned event stream, pages history, handles permissions and queue state, and sends ACP actions directly. Native remains the default renderer.

The renderer uses Pretext-style measurement, memoized row versions, typed-array geometry, binary-search virtualization, scroll anchoring, registry-based React row components, and hot-reloaded theme, layout, and user renderers. The standalone preview includes Claude and Codex recordings, real-speed streaming replay, seeded 5,000-row transcripts, permission and queue fixtures, theme controls, width controls, and fling timing.

Base and recovery

This PR uses the owned base branch feat/acpmux-ts-pane-base, which contains the pre-React acpmux pane snapshot. It does not use or update Lawrence's branches.

The earlier PR #16042 was opened against the wrong stacked base and auto-merged into that parent. This replacement PR is the direct-to-acpmux implementation on an owned base so it can be reviewed and merged independently.

The projections RFC is https://github.com/manaflow-ai/cmuxterm-hq#1051: acpmux owns sessions and event history, Swift hosts, and React and native are both clients.

Preview

cd webviews
bun run preview:dev
bun run preview:build

Static output: webviews/dist/acpmux-agent-session-preview/.

Validation

• bun test src/agent-session/acpmux/model.test.ts src/agent-session/acpmux/direct.test.ts (8 passed)
• bun x tsgo --noEmit
• ./scripts/build-agent-session-web.sh
• ./scripts/build-webviews-app.sh --check
• Swift package tests require macOS CI because this Linux host cannot import the package's existing Darwin dependency.
• Lawrence's native seeded-row fling reference is p50 and p95 8.33 ms at 120 Hz. Comparable TypeScript numbers still require macOS or fleet measurement.

Changelog

Added: React TypeScript agent pane over a direct authenticated acpmux event stream, with a standalone preview harness.

---

Summary by cubic

Adds a React TypeScript agent session pane that renders a direct authenticated acpmux WebSocket stream. Swift stays the WKWebView host and passes the authenticated loopback endpoint, per-launch token, and selected session through a new versioned bridge; React pages the event stream, merges in-flight events with paged history, creates sessions, merges daemon model, mode, and config catalogs, handles prompt acknowledgements and permission and queue state, sends ACP actions, and routes native-only actions (copy, open URL, open file, focus) back through the host bridge.

Lifecycle hardening ignores stale attach replies, session selections, and history pages, persists new sessions before prompting, settles optimistic sends, preserves tool update metadata, computes turn durations, pairs turn summaries without duplicate rows across daemon versions, preserves turn boundaries and duplicate queued prompts with their session defaults, retains implicit turn rows during history replay, keeps fallback transcript events visible during reconnects, and keeps non-edit tool activity visible alongside edited-file details. Every session change reopens the transcript at its latest turn, and the composer stays ready across live snapshots. The transcript uses Pretext measurement aligned with the rendered markdown blocks, coalesces streaming thoughts, binary-search virtualization, memoized rows, cached prepared markdown blocks, code copying, and LCS-based edited-file diff counts. Native rendering remains the default.

Renderer selection

• New app.agentSession.renderer config selects native (default) or TypeScript for new agent session panes; the catalog key placement mirrors the schema nesting so validation stays consistent.
• The session picker refreshes whenever the daemon session list changes, even if the selected session is unchanged, and new agent panes created from command-line tokens now resolve to the configured renderer instead of hardcoding React.

Preview

• Standalone preview at webviews/src/agent-session/acpmux-preview replays recorded Claude and Codex streams with seeded 5,000-row transcripts, permission and queue fixtures, and theme and width controls.

^{Written for commit 00937c1. Summary will update on new commits.}

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[github-actions]

CI failure attribution

CI failed on 00937c1a6e (run 36794029609 attempt 1): 1 code.

Job	Verdict	Why
guards / workflow-guard-tests / preflight	code	a Python test failed

Matched log lines

guards / workflow-guard-tests / preflight: FAIL: test_every_advertised_path_is_supported (__main__.ConfigurationReviewPathsTests.test_every_advertised_path_is_supported)

Not re-run automatically: guards / workflow-guard-tests / preflight is not a machine failure.

Written by scripts/ci/classify_failures.py (ci-failure-attribution.yml); signatures are its SIGNATURES table. A machine verdict is the runner's fault, not this PR's.

[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	npm/​marked@​17.0.5
	npm/​@​chenglou/​pretext@​0.0.9

View full report

[teamleaderleo]

Review at 74231d5: PASS. The fresh review covered direct.ts, App/model, Swift host bridge and session persistence, generated resources, preview fixtures, and purge, selection, reconnect, and attach races. The owned base has no Lawrence ancestry.
Fixed: the replacement preserves the direct acpmux client, generated bundle parity, preview harness, and lifecycle repairs from the merged implementation.
Left: Swift package tests and comparable macOS fling numbers require CI or fleet validation.

[github-actions]

Dogfood tours of 00937c1a

sidebar-and-chrome-tour at 00937c1a: not run

skipped: CI left no app build for this head (its compile failed or was cancelled)

_{Tours are picked by the paths globs in dogfood/scenarios/*.json; a Dogfood-tours: a, b line in the description picks them instead (none turns this off). Look at every frame before merging: a green tour only means no step failed.}

[blacksmith-sh]

Found 2 test failures on Blacksmith runners:

Failures

Test	View Logs
test_every_advertised_path_is_supported (main.ConfigurationReviewPathsTests.test_ev ery_advertised_path_is_supported)/ test_every_advertised_path_is_supported (main.ConfigurationReviewPathsTests.test_ev ery_advertised_path_is_supported)	View Logs
test_list_supported_matches_schema_settings_paths (main.SupportedPathsTests.test_li st_supported_matches_schema_settings_paths)/ test_list_supported_matches_schema_settings_paths (main.SupportedPathsTests.test_li st_supported_matches_schema_settings_paths)	View Logs

^{Need help on this PR? Tag @codesmith-bot with what you need.}