fix(e2e): unblock tags-rename-delete (emit tags-changed + fix selectors)

[h4yfans]

Summary

Three compounding bugs kept the tags-rename-delete.e2e.ts suite red from the moment it was added in #238.

• Product: createNote() only emitted NotesChannels.events.CREATED, never notes:tags-changed. The sidebar's useNoteTagsQuery only invalidates on the latter, so the tag tree never refetched after API-created notes. updateNote() already does this correctly — createNote() was missed when notes.ts was split (refactor(vault): split notes.ts into focused files behind facade (Phase 3.1) #232).
• Test selector: aside button:has-text(...) targets an <aside> element that doesn't exist (the main sidebar is a <div>; only calendar-sidebar.tsx uses <aside>).
• Test setup: the Tags SidebarSection uses defaultExpanded={false}, so even after the tag was indexed and rendered, it wasn't visible to Playwright. The test never expanded the section.

Changes

• apps/desktop/src/main/vault/notes-crud.ts — emit notes:tags-changed from createNote() when mergedTags.length > 0, mirroring updateNote().
• apps/desktop/tests/e2e/tags-rename-delete.e2e.ts — extract expandTagsSection() helper that toggles via aria-label="Tags section, collapsed"; replace aside button:has-text(...) with getByRole('button', { name: tag, exact: true }).

Test plan

• pnpm exec playwright test tests/e2e/tags-rename-delete.e2e.ts — both tests green in 18.8 s locally
• CI shard 3/3 confirms the fix in the larger context
• No regressions in adjacent tag-related tests