VS Code extension session list missing sessions that exist on disk

Bug Description

The VS Code extension's Local session list is not showing all sessions. Sessions are properly written to disk (.jsonl files with valid ai-title entries) but do not appear in the session picker UI. This has been happening consistently for at least 2 weeks.

Evidence

9 sessions exist on disk in ~/.claude/projects/<project>/, but only 6 appear in the VS Code session list. The 3 missing sessions:

| Session ID | Title | Date | Size |
|---|---|---|---|
| b8aaaf20 | Resolve Payoneer automated withdrawal... | Apr 6 | 8.5 MB |
| 145abd5f | Choose webpage for business verification | Mar 30 | 2.5 MB |
| bd72c0b2 | Fill Payoneer Business Details Questionnaire | Mar 30 | 1.8 MB |

All 9 sessions have:

• Same cwd path
• Same entrypoint: "claude-vscode"
• Valid ai-title entries in the .jsonl
• Identical format/structure

There is no observable difference between sessions that appear in the list and those that don't.

Steps to Reproduce

1. Open Claude Code in VS Code
2. Have multiple conversations over several days
3. Open the session list (Local tab)
4. Compare listed sessions vs .jsonl files in ~/.claude/projects/<project>/
5. Some sessions are missing from the UI despite existing on disk

Expected Behavior

All sessions with valid .jsonl files and ai-title entries should appear in the Local session list.

Actual Behavior

Sessions are randomly dropped from the list. No error messages. The user has no way to resume these sessions from VS Code despite the data being fully intact on disk.

Impact

This is a significant usability issue. Users lose access to conversation context and have to re-explain problems from scratch each time. I've hit this bug repeatedly over 2+ weeks — I even have past sessions titled "Debug local chat history disappearing" and "Check project chat history location" from previous attempts to diagnose this same problem.

Environment

• OS: Windows 10 IoT Enterprise LTSC 2021 (10.0.19044)
• VS Code Extension: anthropic.claude-code-2.1.92-win32-x64
• Claude Code versions in sessions: 2.1.81 through 2.1.90
• Shell: bash (Git Bash)