[BUG] Desktop global search doesn't match renamed/pinned session titles

Preflight Checklist

I have searched existing issues and this hasn't been reported yet (closest: #43963 and #39199 cover CLI /resume; #50344 covers the VS Code sidebar; this is the Desktop app's global search)
This is a single bug report
I am using the latest version of Claude Code

What's Wrong?
The Desktop app's global search does not match custom (renamed) session titles. I have a pinned session titled "BRT Descriptive Cache", visible in the Pinned sidebar. Searching "brt desc" — a literal prefix of that title — returns other sessions (including "BRT Research & Dashboard and Reporting", presumably matched via transcript content or auto-generated summary) but not the pinned session whose title is an exact prefix match.

This appears to be the desktop-search manifestation of the known custom-title indexing gap: search matches transcript content and aiTitles but not customTitle values set via rename.

Steps to Reproduce

In the Desktop app, rename a session to a distinctive title (e.g. "BRT Descriptive Cache") and pin it.
Open global search and type a prefix of that title (e.g. "brt desc").
Observe: other sessions appear in results; the renamed/pinned session does not, even though its title is a literal match and it's visible in the sidebar.

Expected Behavior
Search should match against the session's displayed title — custom/renamed titles included — with exact/prefix title matches ranked above content matches.

Environment
Claude Code Desktop app on Windows (latest as of 2026-08-03).

Related: #43963, #39199, #50344, #64304 (divergent title stores), #27195 (renamed titles missing from sessions index)