feat(classification-spine): implement STATE-WP-0065 repo-anchored model

Replace the ad-hoc coordination-domain spine with the Repo Classification
Standard: 14 market domains, classification columns on managed_repos, and
workplans anchored by repo_id (topic_id optional).

- Add Alembic migration d8e9f0a1b2c3 with data backfill and workstream→workplan rename
- Add api/classification.py validation and register-from-classification tooling
- Expose workplan-first REST/MCP surface with legacy workstream aliases
- Add C-24 consistency rule and legacy domain frontmatter mapping
- Update dashboard repos page with category/capability/stake filters
- Update orientation docs; mark STATE-WP-0065 finished

api/schemas/workplan_dependency.py

@@ -0,0 +1,63 @@
+import uuid
+from datetime import datetime
+
+from pydantic import AliasChoices, BaseModel, ConfigDict, Field, computed_field
+
+
+class WorkplanDependencyCreate(BaseModel):
+    to_workplan_id: uuid.UUID | None = Field(
+        default=None,
+        validation_alias=AliasChoices("to_workplan_id", "to_workstream_id"),
+    )
+    to_task_id: uuid.UUID | None = None
+    relationship_type: str = "blocks"
+    description: str | None = None
+
+
+class WorkplanDependencyRead(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
+    id: uuid.UUID
+    from_workplan_id: uuid.UUID
+    to_workplan_id: uuid.UUID | None = None
+    to_task_id: uuid.UUID | None = None
+    relationship_type: str
+    description: str | None = None
+    created_at: datetime
+    updated_at: datetime
+
+
+class WorkplanDepStub(BaseModel):
+    """Minimal projection of the other end of a dependency edge."""
+    dep_id: uuid.UUID
+    target_type: str = "workplan"
+    relationship_type: str = "blocks"
+    workplan_id: uuid.UUID | None = Field(
+        default=None,
+        validation_alias=AliasChoices("workplan_id", "workstream_id"),
+    )
+    workplan_slug: str | None = Field(
+        default=None,
+        validation_alias=AliasChoices("workplan_slug", "workstream_slug"),
+    )
+    workplan_title: str | None = Field(
+        default=None,
+        validation_alias=AliasChoices("workplan_title", "workstream_title"),
+    )
+    task_id: uuid.UUID | None = None
+    task_title: str | None = None
+    description: str | None = None
+
+    @computed_field  # type: ignore[prop-decorator]
+    @property
+    def workstream_id(self) -> uuid.UUID | None:
+        return self.workplan_id
+
+    @computed_field  # type: ignore[prop-decorator]
+    @property
+    def workstream_slug(self) -> str | None:
+        return self.workplan_slug
+
+    @computed_field  # type: ignore[prop-decorator]
+    @property
+    def workstream_title(self) -> str | None:
+        return self.workplan_title