Add state-hub v0.1 — local-first state service for the Custodian

Implements the first live layer of the Custodian cognitive infrastructure:
PostgreSQL schema, FastAPI REST API, FastMCP stdio server, and Observable
Framework telemetry dashboard.

- state-hub/: full stack (docker-compose, FastAPI, Alembic, MCP server, dashboard)
- 5 DB tables: topics, workstreams, tasks, decisions, progress_events
- 11 MCP tools + 5 resources registered in .mcp.json
- Observable dashboard: Overview, Workstreams, Decisions, Progress pages
- CLAUDE.md: session protocol (get_state_summary / add_progress_event ritual)
- ~/.claude/CLAUDE.md: global cross-project reference to the hub
- scripts/pull_image.py: WSL2 TLS-resilient Docker image downloader

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

api/models/progress_event.py

@@ -0,0 +1,43 @@
+import uuid
+from datetime import datetime
+
+from sqlalchemy import DateTime, ForeignKey, String, Text, func
+from sqlalchemy.dialects.postgresql import JSONB, UUID
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+
+from api.models.base import Base, new_uuid
+
+
+class ProgressEvent(Base):
+    """Append-only event log. No updated_at. No DELETE endpoint (constitution §5)."""
+
+    __tablename__ = "progress_events"
+
+    id: Mapped[uuid.UUID] = mapped_column(
+        UUID(as_uuid=True), primary_key=True, default=new_uuid
+    )
+    topic_id: Mapped[uuid.UUID | None] = mapped_column(
+        UUID(as_uuid=True), ForeignKey("topics.id", ondelete="RESTRICT"), nullable=True, index=True
+    )
+    workstream_id: Mapped[uuid.UUID | None] = mapped_column(
+        UUID(as_uuid=True), ForeignKey("workstreams.id", ondelete="RESTRICT"), nullable=True, index=True
+    )
+    task_id: Mapped[uuid.UUID | None] = mapped_column(
+        UUID(as_uuid=True), ForeignKey("tasks.id", ondelete="RESTRICT"), nullable=True, index=True
+    )
+    decision_id: Mapped[uuid.UUID | None] = mapped_column(
+        UUID(as_uuid=True), ForeignKey("decisions.id", ondelete="RESTRICT"), nullable=True, index=True
+    )
+    event_type: Mapped[str] = mapped_column(String(50), nullable=False, index=True)
+    summary: Mapped[str] = mapped_column(Text, nullable=False)
+    detail: Mapped[dict | None] = mapped_column(JSONB, nullable=True)
+    author: Mapped[str | None] = mapped_column(String(100), nullable=True)
+    session_id: Mapped[str | None] = mapped_column(String(100), nullable=True)
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), server_default=func.now(), nullable=False, index=True
+    )
+
+    topic: Mapped["Topic | None"] = relationship("Topic", back_populates="progress_events")  # noqa: F821
+    workstream: Mapped["Workstream | None"] = relationship("Workstream", back_populates="progress_events")  # noqa: F821
+    task: Mapped["Task | None"] = relationship("Task", back_populates="progress_events")  # noqa: F821
+    decision: Mapped["Decision | None"] = relationship("Decision", back_populates="progress_events")  # noqa: F821