[Regression v1.18.3] Web UI sidebar empty, "Nothing here yet" despite /api/session returning 1,125 sessions

Summary

After upgrading to v1.18.3, the web UI at http://localhost:4096/ shows an empty projects sidebar and "Nothing here yet" in the sessions list — even though the backend API returns 1,125 sessions and 22 projects successfully.

This is a regression of the bug originally reported in #30166 and #30801. The fix in PR #30167 ("fix(app): show project sessions before path sync resolves") does not appear to be present in v1.18.3.

Reproduction

1. Have a populated opencode database (any version's data carried forward is fine)
2. Start the server from any directory:

   opencode serve
   

3. Open http://localhost:4096/ (or http://localhost:4096/#/project/global)
4. Observe: left "Projects" sidebar renders empty; main area shows "Nothing here yet / Create a session to get started"

Expected

• Projects sidebar should list all 22 projects
• Sessions panel should list existing sessions
• Clicking /#/project/<any-project-id> should show that project's sessions

Actual

• Projects sidebar is empty (no entries rendered, only "Add project" placeholder)
• Main area shows the empty state ("Nothing here yet")
• Same behavior on /#/project/global and other explicit project URLs
• 0 console errors in browser DevTools

Environment

• opencode: 1.18.3 (Homebrew anomalyco/tap/opencode, installed 2026-07-17)
• OS: macOS (darwin)
• Serve start dir: tested from ~/ and from a project dir
• Browser: latest Chrome, also verified in clean incognito (rules out cache / SW)
• Database: 778MB SQLite, PRAGMA integrity_check returns ok

Related issues

• #30166 — "Sessions list is empty on page load in web UI" (root cause analysis: store.path.directory not bootstrapped when server.connected fires; sortedRootSessions() filters everything out)
• #30801 — same regression, recommended downgrade to 1.15.7
• #35340 — confirmed still broken in 1.17.13, fixes from #30167/#30314/#30804 not cherry-picked to stable
• #27837 — same symptom in web server mode
• #14570 / #14572 — global project (worktree: "/") sidebar empty (related path-canonicalization family)

Workaround (until a fix is released)

• Use the TUI (opencode . from any directory) — fully functional
• Web UI is unusable for browsing existing sessions