feat: Schema Visualizer, docs update & competitor comparison
* chore: add @xyflow/react, dagre, @types/dagre (Task 1)
* feat: add SchemaGraph, TableNode, GraphColumn, Relationship types (Task 2)
* feat: add SchemaGraph, TableNode, GraphColumn, Relationship Rust models (Task 3)
* feat: add cardinality color/label helpers and legend data (Task 4)
* feat: add schema_graph command skeleton with validation (Task 5)
* feat: add PostgreSQL schema graph query builder + cardinality inference (Task 6)
* feat: implement get_schema_graph for PostgreSQL + SQLite (Task 7)
* feat: add getSchemaGraph IPC wrapper (Task 8)
* feat: un-stub Schema Visualizer nav + add view branch placeholder (Task 9)
* feat: add SchemaVisualizerNode custom React Flow table card (Task 10)
* feat: add SchemaVisualizerPage with React Flow canvas (Task 11)
* feat: wire SchemaVisualizerPage + error handling + style polish (Tasks 12-14)
* perf: replace information_schema with pg_catalog for schema graph query (500x+ faster on remote PG)
* fix: add DB selector, ghost-style dropdowns, dark controls, minimap styling, attribution
* fix: always show schema selector, move attribution to top-left
* fix: SelectDropdown close on outside click works in React Flow (capture phase)
* style: remove border from attribution badge
* style: restore bg on attribution, no border
* fix: lower attribution z-index so dropdowns render above
* fix: ensure toolbar + dropdowns stack above canvas attribution
* feat: crow's foot markers on edges + collapsible legend
* fix: restore missing tableCount state (was overwritten by legendOpen)
* fix: move crow's foot marker defs inside ReactFlow SVG, remove duplicate external SVGs
* fix: inject crow's foot SVG markers into ReactFlow SVG via DOM ref
* fix: use hidden SVG before ReactFlow for crow's foot markers, remove DOM injection
* feat: custom CrowsFootEdge component with inline crow's foot markers
* feat: custom CrowsFootEdge with zero-or-one/zero-or-many notation + nullability-based cardinality
* fix: strip markers, use clean text labels only on edges
* fix: add SVG marker defs directly inside ReactFlow + url() references for crow's foot
* fix: use custom CrowsFootEdge with BaseEdge + inline SVG symbols (no marker defs needed)
* debug: add red/green circles at edge endpoints to verify custom edge renders
* fix: remove stale duplicate edge data, use clean data.startMarker/endMarker
* fix: use getSmoothStepPath offset points for correct tangent angle at endpoints
* fix: thicker strokeWidth, position at handle coords, use path tangents
* fix: use straight-line angle (not curve tangent) for marker rotation
* fix: compute marker positions directly with raw math, no SVG transforms
* fix: fixed-orientation symbols — | always vertical, crow's foot fans toward node
* fix: dead simple — | vertical line, ← or → horizontal crow's foot based on edge direction
* fix: increase marker gap to 12px so symbols aren't hidden behind handle dots
* fix: correct offset direction (away from card into gap), G=4
* fix: remove duplicate G offset inside Mark (was canceling out the call-site offset)
* fix: crow's foot back to fork shape — three lines converging to a tip
* fix: flip crow's foot direction
* fix: wider crow's foot spread (4→6)
* feat: add crow's foot symbols to relationship legend
* style: cleaner legend — horizontal edge with endpoint symbols + label
* feat: handles on both sides, edge builder picks closest side based on dagre layout
* fix: compute actual handle distances to pick shortest path
* revert: PK always left, FK always right — one handle per column only
* fix: lock edge marker direction via origRight, TB layout for horizontal spread, truncate long types
* fix: semi-transparent minimap mask, border stroke for viewport visibility
* feat: click edge to highlight (amber glow), all others dim to 15% opacity
* feat: legend highlights matching cardinality row when edge is clicked
* fix: crow's foot symbols now read color from edge style (amber when highlighted)
* fix: highlighted edge gets zIndex 1000 to render on top
* fix: folder empty message now checks unfiltered store, shows filter hint when connections exist but filtered out
* feat: flat SVG DB icons from simple-icons (PostgreSQL, MySQL, SQLite, Redis) replacing emoji
* chore: add *.db, *.sqlite, *.sqlite3 to .gitignore
* docs: update README with 3-way competitor comparison + current roadmap; update AGENTS.md schema visualizer status