#32643 cmux NEXT: the page draws Session Info by default again

Leo, on the shipped native Session Info: "YOU GUYS TREMENDOUSLY FED UP THE SESSION INFO", "WE HAD A 70%" / "NOW IT'S AT FING 10%" / "QUALITY", "IT IS TAKING THIS STUPID FING SPACE FOR NO REASON", and the section header that lost its chevron and drag grip: "WE FING HAD THESE".

The native AppKit port (#31930) shipped on by default in #32159 without the page's section chevrons and ⠿ drag grips, without pushing the layout, without a fit-to-content height, and with a panel background. This turns agent.sessionInfo.native back off by default so the chat page draws Session Info again, as it did before #32159. The native path stays behind its Debug Settings switch until it reaches parity.

Two lines change: the tunable's default and its test (now pageDrawsSessionInfoByDefault). Risk: a person who explicitly turned the Debug switch on keeps the native panel. Spec: design/session-info.md.

Agent session: agent session

🤖 Generated with Claude Code

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Summary by cubic

Draws Session Info from the chat page by default again. The native AppKit panel that shipped on by default was missing the page's section chevrons, drag grips, layout push, and fit-to-content height, so the native path now stays behind the agent.sessionInfo.native Debug Settings switch until it reaches parity. Users who explicitly enabled the native panel keep it.