feat: deeper Wave 2 + observability dashboard

Wave 2 deeper ingestion:
- 6 new Trusted Project State entries from design-level docs:
  p05: test rig architecture, CGH specification, procurement combos
  p06: force control architecture, control channels, calibration loop
- Total state entries: ~23 (was ~17)

Observability:
- GET /admin/dashboard — one-shot system overview: memory counts
  by type/project/status, reinforced count, project state entry
  counts, recent interaction timestamp, extraction pipeline status.
  Replaces the need to query 4+ endpoints to understand system state.

Harness: 17/18 (no regression from new state entries).

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

src/atocore/api/routes.py

@@ -866,6 +866,66 @@ def api_extract_batch(req: ExtractBatchRequest | None = None) -> dict:
     }
 
 
+@router.get("/admin/dashboard")
+def api_dashboard() -> dict:
+    """One-shot system observability dashboard.
+
+    Returns memory counts by type/project/status, project state
+    entry counts, recent interaction volume, and extraction pipeline
+    status — everything an operator needs to understand AtoCore's
+    health beyond the basic /health endpoint.
+    """
+    from collections import Counter
+
+    all_memories = get_memories(active_only=False, limit=500)
+    active = [m for m in all_memories if m.status == "active"]
+    candidates = [m for m in all_memories if m.status == "candidate"]
+
+    type_counts = dict(Counter(m.memory_type for m in active))
+    project_counts = dict(Counter(m.project or "(none)" for m in active))
+    reinforced = [m for m in active if m.reference_count > 0]
+
+    interactions = list_interactions(limit=1)
+    recent_interaction = interactions[0].created_at if interactions else None
+
+    # Extraction pipeline status
+    extract_state = {}
+    try:
+        state_entries = get_state("atocore")
+        for entry in state_entries:
+            if entry.category == "status" and entry.key == "last_extract_batch_run":
+                extract_state["last_run"] = entry.value
+    except Exception:
+        pass
+
+    # Project state counts
+    ps_counts = {}
+    for proj_id in ["p04-gigabit", "p05-interferometer", "p06-polisher", "atocore"]:
+        try:
+            entries = get_state(proj_id)
+            ps_counts[proj_id] = len(entries)
+        except Exception:
+            pass
+
+    return {
+        "memories": {
+            "active": len(active),
+            "candidates": len(candidates),
+            "by_type": type_counts,
+            "by_project": project_counts,
+            "reinforced": len(reinforced),
+        },
+        "project_state": {
+            "counts": ps_counts,
+            "total": sum(ps_counts.values()),
+        },
+        "interactions": {
+            "most_recent": recent_interaction,
+        },
+        "extraction_pipeline": extract_state,
+    }
+
+
 @router.get("/admin/backup/{stamp}/validate")
 def api_validate_backup(stamp: str) -> dict:
     """Validate that a previously created backup is structurally usable."""