Add October 2 changelog entry

[eclairen]

Summary

Adds the October 2 changelog entry covering everything shipped since the September 25 entry.

Every bullet was checked against a merged PR on main (or the equivalent release branch), and against the deployed surface where one could be probed:

• MPP browser purchases verified live — POST /mpp/browsers returns a 402 challenge and /llms.txt advertises the offer.
• The navigator.modelContext polyfill listing and the headful font additions ship in headful v73 / headless v69, which prod hosts are running.
• Browser-first onboarding is unconditional for new users in the dashboard proxy (no flag), and the producer pages it drives are live.
• 1Password Agentic Autofill stays labelled preview; it is still gated per organization.

Not included

Three items were left out because the shipped surface does not match the claim yet:

• AgentCard checkout_origin in the CLI. The CLI support landed after the v0.42.0 tag, so no published CLI has it. The entry credits the MCP server only; add the CLI once v0.43.0 ships.
• Grok Build plugin. The plugin lives in kernel/skills, but the marketplace listing is still an open PR upstream, so the documented grok plugin install kernel path does not work yet.
• Cursor plugin on the hosted MCP server. The plugin change is merged, but it was explicitly prepared for a marketplace re-submission and the listing status could not be confirmed. Easy to add back if the listing is already live.

Configurable TOTP credentials were also held: the API side is deployed, but the MCP and CLI surfaces are not out.

Testing

Docs-only change. No build run — the site has no build step, and every internal link in the entry was confirmed to resolve to an existing page.

🤖 Generated with Claude Code

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Note

Low Risk
Docs-only changelog addition with no runtime or API behavior changes in this PR.

Overview
Adds a new October 2 <Update> block at the top of changelog.mdx, ahead of the September 25 entry, tagged Product and Docs.

The entry documents shipped work since the last release: Auth (1Password Agentic Autofill preview, MCP vault error surfacing, dashboard reauth controls, Unverified connection state), Payments (MPP browser purchases, AgentCard checkout_origin, Link publishable key on vault configs), and Browsers (16GiB pool memory, WebMCP navigator.modelContext polyfill tools, headful Ubuntu fonts, browser-first onboarding).

A separate Documentation updates section lists new or revised guides (1Password, OTLP export, MPP, Code Mode/WebMCP, cookbooks, Web Bot Auth rewrite, pool memory, cookbook nav/skills CLI).

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Project	Status	Preview	Updated
Kernel	🟢 Ready	View Preview	Oct 1, 2026, 9:52 PM

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[ehfeng]

Suggested wording and grouping for the October 2 changelog.