[Bug] Insecure shared temp directory allows cross-user profile access to tasks

Bug Description
There is an issue running cc on multiple user profiles on the same machine. It's weird... the /private/tmp/claude logic is faulty it should be per user profile and the second user profile who run claude should not access the first user profile tmp. it should not be shared between user profiles. it's happened with tasks

Environment Info

• Platform: darwin
• Terminal: iTerm.app
• Version: 2.1.11
• Feedback ID: fcbaa150-da5f-4b0c-8520-114962f7ff21

Errors

[{"error":"Error: EACCES: permission denied, mkdir '/private/tmp/claude/-Users-kobi-projects-safe-file-guardian/tasks'\n    at mkdirSync (node:fs:1342:26)\n    at II0 (file:///Users/kobi/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1552:9150)\n    at ny (file:///Users/kobi/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1552:9927)\n    at GW2 (file:///Users/kobi/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:2292:621)\n    at nC7 (file:///Users/kobi/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:4598:1611)\n    at runNextTicks (node:internal/process/task_queues:65:5)\n    at process.processTimers (node:internal/timers:540:9)\n    at async Object.call (file:///Users/kobi/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:4609:336)\n    at async Ft5 (file:///Users/kobi/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:2700:19680)","timestamp":"2026-01-17T05:53:26.133Z"}]