feat(capability-requests): add cross-domain capability catalog and request routing

Introduces a capability catalog (CUST-WP-0022) so domains can advertise what
they provide and agents can request capabilities from other domains with
auto-routing, lifecycle tracking, and task-unblocking on completion.

- New models: CapabilityCatalog, CapabilityRequest with full lifecycle
  (requested → accepted → in_progress → ready_for_review → completed/rejected/withdrawn)
- Migration i6d7e8f9a0b1: capability_catalog + capability_requests tables
- Router /capability-catalog and /capability-requests with accept/status endpoints
- 7 new MCP tools: register_capability, list_capabilities, request_capability,
  accept_capability_request, update_capability_request_status,
  list_capability_requests, get_capability_request
- StateSummary gains open_capability_requests count
- Dashboard: capability-requests.md page + docs/capabilities.md + docs/scope.md
- SCOPE.md: three seed capabilities documented (MCP registration, state tracking, SBOM)
- scope.template: Provided Capabilities section with example block
- scripts/ingest_capabilities.py + make ingest-capabilities[/-all] targets

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

api/models/__init__.py

@@ -15,6 +15,8 @@ from api.models.contribution import Contribution, ContributionType, Contribution
 from api.models.sbom_snapshot import SBOMSnapshot
 from api.models.sbom_entry import SBOMEntry, Ecosystem
 from api.models.agent_message import AgentMessage
+from api.models.capability_catalog import CapabilityCatalog
+from api.models.capability_request import CapabilityRequest
 
 __all__ = [
     "Base",
@@ -34,4 +36,6 @@ __all__ = [
     "SBOMSnapshot",
     "SBOMEntry", "Ecosystem",
     "AgentMessage",
+    "CapabilityCatalog",
+    "CapabilityRequest",
 ]

api/models/capability_catalog.py

@@ -0,0 +1,39 @@
+import uuid
+
+from sqlalchemy import ARRAY, ForeignKey, String, Text, UniqueConstraint
+from sqlalchemy.dialects.postgresql import UUID
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+
+from api.models.base import Base, TimestampMixin, new_uuid
+
+
+class CapabilityCatalog(Base, TimestampMixin):
+    __tablename__ = "capability_catalog"
+    __table_args__ = (
+        UniqueConstraint("domain_id", "capability_type", "title", name="uq_catalog_domain_type_title"),
+    )
+
+    id: Mapped[uuid.UUID] = mapped_column(
+        UUID(as_uuid=True), primary_key=True, default=new_uuid
+    )
+    domain_id: Mapped[uuid.UUID] = mapped_column(
+        UUID(as_uuid=True),
+        ForeignKey("domains.id", ondelete="RESTRICT"),
+        nullable=False,
+        index=True,
+    )
+    capability_type: Mapped[str] = mapped_column(String(50), nullable=False)
+    title: Mapped[str] = mapped_column(String(255), nullable=False)
+    description: Mapped[str | None] = mapped_column(Text, nullable=True)
+    keywords: Mapped[list[str]] = mapped_column(
+        ARRAY(String), nullable=False, server_default="{}"
+    )
+    status: Mapped[str] = mapped_column(
+        String(20), nullable=False, default="active", server_default="active"
+    )
+
+    domain: Mapped["Domain"] = relationship("Domain", lazy="selectin")  # noqa: F821
+
+    @property
+    def domain_slug(self) -> str:
+        return self.domain.slug if self.domain is not None else ""

api/models/capability_request.py

@@ -0,0 +1,93 @@
+import uuid
+from datetime import datetime
+
+from sqlalchemy import DateTime, ForeignKey, String, Text
+from sqlalchemy.dialects.postgresql import UUID
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+
+from api.models.base import Base, TimestampMixin, new_uuid
+
+
+class CapabilityRequest(Base, TimestampMixin):
+    __tablename__ = "capability_requests"
+
+    id: Mapped[uuid.UUID] = mapped_column(
+        UUID(as_uuid=True), primary_key=True, default=new_uuid
+    )
+    title: Mapped[str] = mapped_column(String(500), nullable=False)
+    description: Mapped[str | None] = mapped_column(Text, nullable=True)
+    capability_type: Mapped[str] = mapped_column(String(50), nullable=False)
+    priority: Mapped[str] = mapped_column(
+        String(20), nullable=False, default="medium", server_default="medium"
+    )
+    status: Mapped[str] = mapped_column(
+        String(20), nullable=False, default="requested", server_default="requested"
+    )
+
+    # Requester side
+    requesting_domain_id: Mapped[uuid.UUID] = mapped_column(
+        UUID(as_uuid=True),
+        ForeignKey("domains.id", ondelete="RESTRICT"),
+        nullable=False,
+        index=True,
+    )
+    requesting_workstream_id: Mapped[uuid.UUID | None] = mapped_column(
+        UUID(as_uuid=True),
+        ForeignKey("workstreams.id", ondelete="SET NULL"),
+        nullable=True,
+    )
+    requesting_agent: Mapped[str] = mapped_column(String(100), nullable=False)
+
+    # Fulfiller side (populated on accept / auto-route)
+    fulfilling_domain_id: Mapped[uuid.UUID | None] = mapped_column(
+        UUID(as_uuid=True),
+        ForeignKey("domains.id", ondelete="SET NULL"),
+        nullable=True,
+        index=True,
+    )
+    fulfilling_workstream_id: Mapped[uuid.UUID | None] = mapped_column(
+        UUID(as_uuid=True),
+        ForeignKey("workstreams.id", ondelete="SET NULL"),
+        nullable=True,
+    )
+    fulfilling_agent: Mapped[str | None] = mapped_column(String(100), nullable=True)
+
+    # Links
+    blocking_task_id: Mapped[uuid.UUID | None] = mapped_column(
+        UUID(as_uuid=True),
+        ForeignKey("tasks.id", ondelete="SET NULL"),
+        nullable=True,
+    )
+    catalog_entry_id: Mapped[uuid.UUID | None] = mapped_column(
+        UUID(as_uuid=True),
+        ForeignKey("capability_catalog.id", ondelete="SET NULL"),
+        nullable=True,
+    )
+
+    resolution_note: Mapped[str | None] = mapped_column(Text, nullable=True)
+    accepted_at: Mapped[datetime | None] = mapped_column(
+        DateTime(timezone=True), nullable=True
+    )
+    completed_at: Mapped[datetime | None] = mapped_column(
+        DateTime(timezone=True), nullable=True
+    )
+
+    # Relationships
+    requesting_domain: Mapped["Domain"] = relationship(  # noqa: F821
+        "Domain", foreign_keys=[requesting_domain_id], lazy="selectin"
+    )
+    fulfilling_domain: Mapped["Domain | None"] = relationship(  # noqa: F821
+        "Domain", foreign_keys=[fulfilling_domain_id], lazy="selectin"
+    )
+    blocking_task: Mapped["Task | None"] = relationship("Task", lazy="selectin")  # noqa: F821
+    catalog_entry: Mapped["CapabilityCatalog | None"] = relationship(  # noqa: F821
+        "CapabilityCatalog", lazy="selectin"
+    )
+
+    @property
+    def requesting_domain_slug(self) -> str:
+        return self.requesting_domain.slug if self.requesting_domain else ""
+
+    @property
+    def fulfilling_domain_slug(self) -> str | None:
+        return self.fulfilling_domain.slug if self.fulfilling_domain else None