Persist sessions server-side / decouple work from window lifecycle

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Today the Claude Code session is bound to the active window/tab. If the user closes it (accidentally or to switch context), in-flight tool calls die mid-stream and the user has to summarize "what we were doing" to a fresh context.

Proposed Solution

Proposal: run the agent loop server-side, with the window as a thin front-end that subscribes to a session ID. Closing the window pauses display only — the agent keeps running (or holds state until reconnected). Reopening with a session URL resumes mid-task with full transcript.

Side benefits:

Resume from another machine.
Multiple windows on the same session.
Long-running work (refactors across many files) doesn't fight the laptop sleeping.

Alternative Solutions

_No response_

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

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Additional Context

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