refactor(ui): share collapsible workflow field cards
Filter rules, sort rules, document tags and knowledge tag filters repeat the same collapsible field-card styling. Migrate them to EMCN CollapsibleCard, add a header-actions slot outside the collapse target, and forward native root attributes so workflow search can still target each row.
Card colors, borders, corners, spacing and action positions are preserved. Long titles adopt the existing fade/full-title tooltip treatment. Field controls, search highlights, refs, read-only restrictions and add/remove behavior stay in the consumers. No new visual variants are introduced.
Validation: 345 EMCN tests and 118 existing fork-sync/search-highlight tests pass, as do workspace type checks/lint, import resolution and API validation. The external audit removes all eight scoped radius findings with zero new findings. Ten light/dark fixture comparisons confirm unchanged card/body geometry and action positions, including the existing shared-card preview layout. Browser checks cover keyboard toggling and independent action clicks; full product workflow and landing integrations were not exercised. Review tooling and screenshots are outside this PR.