fix(tui): request root sessions in session dialog

[codeg-dev]

Issue for this PR

Closes #16270
Related: #13877, #25897, #23276

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

The session switch dialog was rendering root sessions from the shared mixed session bootstrap list. In projects with many recent child/subagent sessions, the server-side limit can be filled before the dialog filters out child sessions, so root sessions disappear from /sessions even though opencode session list can still show them.

This keeps the shared sync.data.session bootstrap unchanged, because other TUI flows use it for parent/child navigation. The dialog now has its own root-session query for both the default picker and search results, preserving the current scope/path filter while passing roots: true.

The default dialog query asks for the latest 100 root sessions instead of reusing the bootstrap 30-day window. Search asks for the latest 30 matching root sessions. Delete and workspace recovery paths refetch the dialog root-session resource so the picker stays current.

How did you verify your code works?

• bun test test/cli/tui/dialog-session-list.test.ts test/server/session-list.test.ts test/server/httpapi-sdk.test.ts --timeout 30000
• bun run typecheck
• bun run build
• Manual driver: imported createDialogSessionListQuery and verified the default picker query is { scope: "project", roots: true, limit: 100 } with no start/search, and the search query preserves path filters with roots: true, limit: 30, and search.

Screenshots / recordings

N/A. This changes the session query used by the TUI dialog, not the rendered UI layout.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

Authorship disclosure: prepared with AI assistance.

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Based on my search, I found a related PR that should be reviewed:

PR #23276: fix(tui): request root sessions in switch session dialog
#23276

This PR appears to be a prior/related fix addressing a very similar issue with requesting root sessions in the session dialog. It's referenced in the current PR's description under "Related: #13877, #25897, #23276". The current PR (26432) may be building upon or refining the approach from #23276.

This should be cross-referenced to understand if there's overlapping logic or if the current PR supersedes the previous approach.

[codeg-dev]

Context on #23276 overlap:

This is intentionally close to #23276's narrow-dialog approach, but it adds two differences that should help avoid the earlier stale/template/design problems:

1. The default dialog query does not include the bootstrap 30-day start filter. It asks for the latest 100 root sessions directly, which better matches the CLI root-session behavior and addresses reports where older root sessions are hidden.
2. The root-query construction is covered by test/cli/tui/dialog-session-list.test.ts, so the dialog-specific scope is explicit and protected.

It still keeps the important design constraint from the #24383 discussion: the shared sync.data.session bootstrap remains mixed and unchanged for parent/child navigation.

Authorship disclosure: prepared with AI assistance.