Adds aria and keyboard interaction tests for the Dialog component (10 new tests, 53 total passing). Also fixes DialogContent to render with the `open` attribute so the <dialog> element is accessible in JSDOM.
Implements DialogRoot, Content, Title, Description, Trigger, Close, Portal, and Overlay parts with full context wiring, focus trap, scroll lock, and dismiss. Also fixes pre-existing TS6 exactOptionalPropertyTypes errors in create-disclosure-state and presence, and silences TS6.0 deprecation warnings via ignoreDeprecations.
Implements the controlled/uncontrolled state primitive with full TDD coverage (5 tests passing). Delegates to an internal signal when uncontrolled, defers to the external value accessor when controlled.
