Generate AI-summarized titles for sessions in --resume picker

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

When using claude --resume, each session is labeled with the last user message. This makes it very hard to identify which session
is which, because the last message is often generic or irrelevant to the session's actual topic — things like "hello",
"continue", "got it", or a long follow-up question truncated mid-sentence.

For users who run multiple sessions throughout the day, scanning 10+ sessions labeled this way is painful. You end up opening
sessions blindly just to check what they were about.

Proposed Solution

Automatically generate a short AI-summarized title for each session (e.g., "Debugging auth middleware" or "Setting up MCP
config"), similar to how Claude Desktop and claude.ai already generate conversation titles.

The title could be generated lazily — after the first few exchanges or when the session is saved — to avoid adding latency to the
interactive experience. It would replace the current "last user message" as the default display in the --resume picker.

Alternative Solutions

Currently I use Ctrl+R to manually rename important sessions, but this is easy to forget and doesn't scale. It also requires me
to remember to do it before ending the session.

Another option would be using the first user message instead of the last, which is slightly better since it often contains the
initial task description — but an AI-generated summary would be far more accurate and consistent.

Priority

Medium - Would be very helpful

Feature Category

CLI commands and flags

Use Case Example

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Additional Context

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