[Bug] Prompt caching not properly persisting across sessions with large contexts

Bug Description
Something must be still off with your caching. I had a big context (56% use of the 1million window) on Opus 4.7, ran out of my 5 hour limit, had to go away for 4 hours, came back, sent one message and it costed me 25% of my current limit window's use. Very frustrating and unfair.

Environment Info

• Platform: linux
• Terminal: ghostty
• Version: 2.1.124
• Feedback ID: 15ffc0ac-a849-4d07-a1d2-56b32419dd38

Errors

[{"error":"Error: NON-FATAL: Lock acquisition failed for /home/zsoltjanos/.local/share/claude/versions/2.1.124 (expected in multi-process scenarios)\n    at n68 (/$bunfs/root/src/entrypoints/cli.js:2770:2177)\n    at aM6 (/$bunfs/root/src/entrypoints/cli.js:2770:1257)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-30T06:30:15.253Z"},{"error":"Error: Request was aborted.\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:50:3448)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-30T08:11:11.834Z"}]