feat: support async command results

[rhnvrm]

Summary

• add data-filter="manual" for application- and server-supplied Command results
• emit cancelable oatbase:query events with the trimmed query and expose query plus refresh()
• reindex dynamic results while synchronizing listbox roles, active state, empty state, groups, selection, and aria-activedescendant
• document the async ownership boundary and ship focused browser/accessibility coverage

Verification

• bun test (52 passed)
• browser smoke: component fixture and documentation fixture
• Chromium component suite (25 passed, including axe, keyboard, themes, contrast, and visual baselines)
• package dry run
• complete bundle: 27,248 gzip bytes (28,000 budget)
• extensions bundle: 17,606 gzip bytes (18,000 budget)