feat(app): add workflow graph modal for subagent session tree

[yashranaway]

Closes #1763

Summary

• Add a new WorkflowGraphModal that renders the parent/child session hierarchy for the current workspace as a tree of cards. Each card shows the session title, a status dot, and a "{count} subagent(s)" badge when the subtree has children, with a CSS connector line linking parents to their children.
• Wire a View workflow graph entry into the React command palette (next to the settings tabs) so the modal is one ⌘+K stroke away. The entry is rendered conditionally and only appears when a workspace is selected, so it stays out of the way on the welcome surface.
• Reuse the existing buildSessionTreeState helper from the sidebar so the modal and the sidebar agree on what counts as a parent/child relationship and which subtree is active. No new data plumbing, no new server call.
• Click on any card closes the modal and navigates to that session, matching the reporter requirement to click into a sub-session conversation directly from the graph view.

Verification

• node scripts/i18n-audit.mjs --ci passes with the new session.workflow_graph_* and session.cmd_workflow_graph_* keys added.
• pnpm --filter @openwork/app typecheck currently fails on the same pre-existing origin/dev errors in messaging-view-state.ts, app-sidebar.tsx, and settings-route.tsx (lines 1324-1557); this branch does not touch those files.
• Local Electron run with OPENWORK_DEV_MODE=1 pnpm dev: created a workspace, sent a prompt that spawned subagents via the task tool, opened the modal from ⌘+K → "View workflow graph". The tree renders with both root sessions and their subagent children connected by the indent line, and each card navigates back to its session on click.

Screenshot

Notes

• Out of scope: live progress animation, true DAG cross-tree edges (sessions form a strict tree by data model — each session has a single parentID), and visual-regression tests. The modal subscribes to the same reactive workspaceSessionGroups snapshot the sidebar uses, so changes propagate on the next re-render without a dedicated stream.
• The trigger lives in the palette rather than the sidebar header so this PR avoids touching the in-flight shadcn migration surfaces. Happy to add a sidebar button as a follow-up once that area settles.

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
openwork-landing	Ready	Preview, Comment, Open in v0	May 22, 2026 4:10pm

[vercel]

@yashranaway is attempting to deploy a commit to the Different AI Team on Vercel.

A member of the Team first needs to authorize it.