[Lampese]

Related issue

Same-repository UI bug fix reported by the user.

Problem / pressure

Clicking the session header's ⋯ button highlighted Full width while the pointer was still on the trigger. Its nested switch was the first tabbable descendant, so the menu's initial focus selected the switch and highlighted the containing row.

Summary

Keep the trailing switch outside the tab order so the menu row owns keyboard navigation. Pointer opening focuses the menu surface without preselecting an action; keyboard opening, hover, row activation, and direct switch clicks remain available. The preference changes only on activation, and the menu stays open when it is toggled.

Visual explanation

SessionHeaderMenu
└─ Menu.Content       ← receives initial focus on pointer opening
   └─ Full width row  ← keyboard navigation and activation
      └─ Switch       ← tabIndex=-1; still directly clickable

The screenshot uses the existing synthetic Storybook fixture. It omits optional Share and owner-transfer callbacks; the production entries and their visibility conditions are unchanged.

Before / after

Before	After
Opening with the mouse immediately highlighted Full width.	No action is highlighted until pointer hover or keyboard navigation.
The nested switch could claim initial focus.	The menu row owns keyboard navigation; both row and switch still toggle once without dismissing the menu.

Test plan

• Passed: NODE_ENV=test pnpm --filter @lody/components exec vitest run tests/session-header-menu.test.tsx tests/conversation-wide-mode.test.tsx — 15 tests.
• Passed: browser checks against the real SessionHeaderMenu Storybook component for pointer opening, keyboard opening, hover, row activation, direct switch clicks, and Escape dismissal.
• Passed: pnpm format.
• Passed: pnpm check — workspace type checking, typed and Effect lint, all configured workspace tests, i18n validation, and boundary guards.
• pnpm run docs check reports six pre-existing missing Kimi/Pi submodule links in the bilingual subagent-events note; no new broken links or protected-topic changes.

Context handoff

This is a focused fix on a same-repository branch. The owning session README and bilingual bug-fix note document the focus boundary and verification. Optional menu actions, their callbacks, and capability checks are unchanged.