[Bug] Local session transcript stops persisting mid-session despite continued active usage

Bug Description
Local session transcript stops persisting despite continued real usage under the same session identity Local Claude Code session fcb73d7e-ba1d-470f-aaa8-166210ad958f (project: retirement-finance-app) has a fully intact, uncorrupted local transcript (verified line-by-line, zero corrupted lines) — but its last real conversational entry is dated 2026-08-21T19:02:21Z. Real work continued under this same session identity after that date: a git commit in the project repo dated 2026-09-02 carries the trailer Claude-Session: https://claude.ai/code/session_01LB8xodxfvxvYyDEi2BmiUw — the exact same bridge session ID recorded in the local transcript's own bridge-session metadata line. So the session was actively and successfully used for roughly two more weeks after local persistence apparently stopped. I recall a context-compaction event occurring in that PowerShell session at least a couple of times during the two weeks. I only ever used this session via the PowerShell CLI on one machine — no other device, no WSL (confirmed not installed on this machine), no web interface. Separately: the account that owned this session was later disabled/subscription-cancelled, and https://claude.ai/code/session_01LB8xodxfvxvYyDEi2BmiUw now redirects to /code/disabled rather than 404ing — suggesting the session and its full history (including the ~2 weeks missing locally) still exist server-side, just currently inaccessible. So it appears as if Claude Code was failing to persist to the local transcript file while the session continued to function normally server-side. This resulted in what felt like ~2 weeks of local work going missing even though nothing was actually lost server-side. This is already being handled via Support (conversation ID 215475786992130) for the account-access side; this report is specifically about the local-persistence gap as a product bug.

Environment Info

• Platform: win32
• Terminal: windows-terminal
• Version: 2.1.260
• Feedback ID: a47190ea-bf29-4373-904a-92f4a4724789

Errors

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