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/models/workstream_dependency.py

@@ -1,75 +1,6 @@
-import uuid
+"""Backward-compatibility shim — prefer ``api.models.workplan_dependency``."""
+from api.models.workplan_dependency import WorkplanDependency
 
-from sqlalchemy import CheckConstraint, ForeignKey, Index, String, Text, text
-from sqlalchemy.dialects.postgresql import UUID
-from sqlalchemy.orm import Mapped, mapped_column, relationship
+WorkstreamDependency = WorkplanDependency
 
-from api.models.base import Base, TimestampMixin, new_uuid
-
-
-class WorkstreamDependency(Base, TimestampMixin):
-    """Directed dependency edge: `from_workstream` depends on a workstream or task.
-
-    Semantics: the target must reach a satisfactory state before `from_workstream`
-    can fully proceed.  Hard deletes are intentional —
-    removing an edge removes a constraint, not information.
-    """
-
-    __tablename__ = "workstream_dependencies"
-    __table_args__ = (
-        CheckConstraint(
-            "(to_workstream_id IS NOT NULL AND to_task_id IS NULL) "
-            "OR (to_workstream_id IS NULL AND to_task_id IS NOT NULL)",
-            name="ck_ws_dep_exactly_one_target",
-        ),
-        Index(
-            "uq_ws_dep_workstream_target",
-            "from_workstream_id",
-            "to_workstream_id",
-            "relationship_type",
-            unique=True,
-            postgresql_where=text("to_workstream_id IS NOT NULL"),
-        ),
-        Index(
-            "uq_ws_dep_task_target",
-            "from_workstream_id",
-            "to_task_id",
-            "relationship_type",
-            unique=True,
-            postgresql_where=text("to_task_id IS NOT NULL"),
-        ),
-    )
-
-    id: Mapped[uuid.UUID] = mapped_column(
-        UUID(as_uuid=True), primary_key=True, default=new_uuid
-    )
-    from_workstream_id: Mapped[uuid.UUID] = mapped_column(
-        UUID(as_uuid=True),
-        ForeignKey("workstreams.id", ondelete="CASCADE"),
-        nullable=False,
-        index=True,
-    )
-    to_workstream_id: Mapped[uuid.UUID | None] = mapped_column(
-        UUID(as_uuid=True),
-        ForeignKey("workstreams.id", ondelete="CASCADE"),
-        nullable=True,
-        index=True,
-    )
-    to_task_id: Mapped[uuid.UUID | None] = mapped_column(
-        UUID(as_uuid=True),
-        ForeignKey("tasks.id", ondelete="CASCADE"),
-        nullable=True,
-        index=True,
-    )
-    relationship_type: Mapped[str] = mapped_column(
-        String(40), nullable=False, default="blocks", server_default="blocks", index=True
-    )
-    description: Mapped[str | None] = mapped_column(Text, nullable=True)
-
-    from_workstream: Mapped["Workstream"] = relationship(  # noqa: F821
-        "Workstream", foreign_keys=[from_workstream_id]
-    )
-    to_workstream: Mapped["Workstream | None"] = relationship(  # noqa: F821
-        "Workstream", foreign_keys=[to_workstream_id]
-    )
-    to_task: Mapped["Task | None"] = relationship("Task", foreign_keys=[to_task_id])  # noqa: F821
+__all__ = ["WorkstreamDependency", "WorkplanDependency"]