[Bug] Session context corruption with cache/away_summary restoration causing cross-contaminated responses

Bug Description
Title:
Claude Code session context appears corrupted / possible wrong cache or summary restoration

Product:
Claude Code CLI

Version:
2.1.169

Session ID:
eba0727a-8a00-4a97-8fc1-3e829172bd02

Summary:
A Claude Code session started answering based on context that was not present in my user messages.
It generated responses about GitHub Discussions, MEMORY.md, docs/ai-logs, "素直か!", and "モンテカルロ", none of
which were part of my actual request flow.

Concern:
This may be context/cache/away_summary corruption. I am also concerned about possible cross-session or cross-user
context contamination.

Evidence:

• User asked only about app specs / screen transitions.
• Later responses ignored latest user messages.
• Several assistant turns show input_tokens: [REDACTED] with very large cache_read_input_tokens.
• away_summary included claims not present in actual user messages.
• The session became unrecoverable; new prompts received emoji or unrelated replies.

Relevant log lines:
71 -> 80: user asks "どういう状況？", assistant answers about GitHub Discussions.
92/94 -> 96: user says no work was requested, assistant says MEMORY.md was deleted.
146 -> 148: user asks why it cannot answer, assistant replies "モンテカルロにやられました".
173 -> 181: user asks to organize conversation / answer in Japanese, assistant replies emoji / unrelated text.
184: away_summary says "素直か!" loop, but no such user message exists.

Environment Info

• Platform: darwin
• Terminal: ghostty
• Version: 2.1.169
• Feedback ID: 32b2e087-4e31-4ae5-992c-33fd90208dc6

Errors

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