fix(browser): gate manual-login profile setup

[pdurlej]

Summary

• Fail fast when browser manual-login mode points at an uninitialized private Oracle Chrome profile and the run is not an explicit setup run.
• Cap non-setup manual-login waits so MCP/Claude callers get an actionable login/setup error instead of hanging until the browser timeout.
• Expand MCP dry-run/tool guidance to explain that manual-login uses a private Oracle Chrome profile separate from the user's normal Chrome, with the exact first-time setup command.
• Clarify README first-time login copy.
• Format scripts/build-docs-site.mjs with oxfmt so current pnpm run format:check passes on upstream main.

Why

A Claude Code MCP browser consult can resolve to manual-login mode with a private profile that has never been signed into ChatGPT. Before this change, Oracle could open that separate Chrome profile, wait for login until the MCP client timed out, and leave the caller with a generic timeout or closed-window error.

The intended path should be explicit: first run setup with --browser-keep-browser, or use --browser-attach-running to reuse an already signed-in Chrome.

Tests

• pnpm vitest run tests/browser/index.test.ts tests/mcp/consult.test.ts tests/browser/pageActions.test.ts
• pnpm run format:check
• pnpm run build
• pnpm run check
• pnpm test
• git diff --check

Smoke

• Empty manual-login profile smoke exits immediately with browser-login-setup guidance and no long Chrome wait.