feat: implement Story 1.1 — create and view diagrams

Add diagram/project DB schema, CRUD API, dashboard pages with grid/card/
empty state, create dialog with type selector, editor placeholder, and
26 schema validation tests. Includes code review fixes: soft-delete
filter on GET /:id, error handling, keyboard accessibility, type-safe
API response types, and error states on pages.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

_bmad-output/implementation-artifacts/sprint-status.yaml

@@ -0,0 +1,110 @@
+# generated: 2026-02-22
+# project: domaingraph
+# project_key: NOKEY
+# tracking_system: file-system
+# story_location: {project-root}/_bmad-output/implementation-artifacts
+
+# STATUS DEFINITIONS:
+# ==================
+# Epic Status:
+#   - backlog: Epic not yet started
+#   - in-progress: Epic actively being worked on
+#   - done: All stories in epic completed
+#
+# Epic Status Transitions:
+#   - backlog → in-progress: Automatically when first story is created (via create-story)
+#   - in-progress → done: Manually when all stories reach 'done' status
+#
+# Story Status:
+#   - backlog: Story only exists in epic file
+#   - ready-for-dev: Story file created in stories folder
+#   - in-progress: Developer actively working on implementation
+#   - review: Ready for code review (via Dev's code-review workflow)
+#   - done: Story completed
+#
+# Retrospective Status:
+#   - optional: Can be completed but not required
+#   - done: Retrospective has been completed
+#
+# WORKFLOW NOTES:
+# ===============
+# - Epic transitions to 'in-progress' automatically when first story is created
+# - Stories can be worked in parallel if team capacity allows
+# - SM typically creates next story after previous one is 'done' to incorporate learnings
+# - Dev moves story to 'review', then runs code-review (fresh context, different LLM recommended)
+
+generated: 2026-02-22
+project: domaingraph
+project_key: NOKEY
+tracking_system: file-system
+story_location: "{project-root}/_bmad-output/implementation-artifacts"
+
+development_status:
+  # ── Epic 1: Workspace & Diagram Management (Phase 1 - Foundation) ──
+  epic-1: in-progress
+  1-1-create-and-view-diagrams: done
+  1-2-organize-diagrams-into-projects: backlog
+  1-3-diagram-access-control-and-management: backlog
+  1-4-recent-view-and-drag-and-drop-organization: backlog
+  epic-1-retrospective: optional
+
+  # ── Epic 2: Interactive Canvas & Diagram Types (Phase 2) ──
+  epic-2: backlog
+  2-1-canvas-workspace-with-xyflow-react-and-unified-graph-model: backlog
+  2-2-elk-js-auto-layout-engine-in-web-worker: backlog
+  2-3-bpmn-diagram-type-renderer: backlog
+  2-4-entity-relationship-diagram-type-renderer: backlog
+  2-5-org-chart-diagram-type-renderer: backlog
+  2-6-architecture-diagram-type-renderer: backlog
+  2-7-sequence-diagram-type-renderer: backlog
+  2-8-flowchart-diagram-type-renderer: backlog
+  2-9-node-selection-and-manual-repositioning: backlog
+  epic-2-retrospective: optional
+
+  # ── Epic 3: AI Copilot & Chat (Phase 2) ──
+  epic-3: backlog
+  3-1-chat-panel-ui-with-streaming-ai-responses: backlog
+  3-2-ai-diagram-generation-from-natural-language: backlog
+  3-3-badge-based-element-referencing-for-targeted-modifications: backlog
+  3-4-ai-semantic-suggestions-and-accept-reject-workflow: backlog
+  3-5-new-diagram-wizard-with-ai-type-inference-and-chat-first-onboarding: backlog
+  3-6-hover-affordances-and-command-palette: backlog
+  epic-3-retrospective: optional
+
+  # ── Epic 4: Real-Time Collaboration (Phase 2) ──
+  epic-4: backlog
+  4-1-liveblocks-room-setup-with-zustand-store-integration: backlog
+  4-2-live-cursors-and-presence-indicators: backlog
+  4-3-crdt-conflict-free-concurrent-editing: backlog
+  4-4-element-pinned-comments: backlog
+  4-5-ai-soft-lock-and-crdt-mutation-pipeline: backlog
+  epic-4-retrospective: optional
+
+  # ── Epic 5: Voice Input & Audio Annotations (Phase 2) ──
+  epic-5: backlog
+  5-1-voice-input-with-deepgram-stt: backlog
+  5-2-audio-annotation-recording-and-playback: backlog
+  5-3-annotation-types-panel-and-tts-readback: backlog
+  5-4-presentation-mode-and-annotation-export: backlog
+  epic-5-retrospective: optional
+
+  # ── Epic 6: Export, Sharing & Distribution (Phase 2) ──
+  epic-6: backlog
+  6-1-png-and-svg-image-export: backlog
+  6-2-json-and-sql-ddl-data-export: backlog
+  6-3-shareable-links-with-no-auth-access: backlog
+  epic-6-retrospective: optional
+
+  # ── Epic 7: Nested Diagrams (Phase 3 - after Epics 2+3) ──
+  epic-7: backlog
+  7-1-cross-type-nested-diagram-containers: backlog
+  7-2-drill-down-navigation-with-breadcrumbs: backlog
+  7-3-ai-parent-context-awareness-and-depth-limits: backlog
+  epic-7-retrospective: optional
+
+  # ── Epic 8: Analytics, Rate Limiting & Platform Operations (Phase 2 - independent) ──
+  epic-8: backlog
+  8-1-posthog-core-event-tracking: backlog
+  8-2-ai-rate-limiting-for-free-tier: backlog
+  8-3-admin-dashboard-integration-and-error-monitoring: backlog
+  epic-8-retrospective: optional