feat: onboard React Flow documentation views

references/local-yaml-data-database.md

@@ -105,12 +105,21 @@ id: feature-001
 title: Display project lifecycle state
 status: in-progress
 epic_id: epic-001
+depends_on_feature_ids:
+  - feature-000
+roadmap:
+  start: 2026-08-01
+  end: 2026-08-21
+  lane: portal
+  progress: 60
 summary: >
   Display the current lifecycle state and supporting evidence.
 owners:
   - root-at-skic
 ```
 
+`depends_on_feature_ids` is the canonical Feature dependency field. `roadmap` is optional unless the documentation exposes a date-based roadmap. When present, validate ISO dates, require `end` not to precede `start`, require a stable lane, and constrain `progress` to 0–100. React Flow adapters may derive dependency edges and Gantt-like positions from these fields; TSX and MDX must not maintain separate schedules or dependency lists.
+
 ### Task
 
 A Task belongs to one Feature. The Task owns that relationship through `feature_id`.
@@ -267,6 +276,8 @@ Validation must fail for:
 - an unknown entity type, status, or requirement category;
 - a required field with an empty value;
 - a dangling `epic_id`, `feature_id`, or entry in `feature_ids`;
+- a dangling entry in `depends_on_feature_ids`;
+- an invalid roadmap date, reversed date range, missing lane, or progress outside 0–100;
 - an index entry whose record is missing;
 - a record missing from its collection index;
 - a stale relationship index;
@@ -386,6 +397,7 @@ For schema evolution, increment `schema_version`, migrate all records and indexe
 - [ ] Every entity has one stable-ID record file.
 - [ ] Every leaf collection has a deterministic `index.yml`.
 - [ ] Canonical relationship fields implement Epic → Feature → Task and n:m mappings to requirements and architectural decisions.
+- [ ] Feature dependencies and optional roadmap scheduling remain in source YAML and pass referential and date-range validation.
 - [ ] Reverse indexes are generated, committed, and stale-index checked.
 - [ ] Referential validation rejects duplicate and dangling IDs.
 - [ ] Docusaurus loads data at build time.