feat: Phase 2 Memory Core — structured memory with context integration

Memory Core implementation:
- Memory service with 6 types: identity, preference, project, episodic, knowledge, adaptation
- CRUD operations: create (with dedup), get (filtered), update, invalidate, supersede
- Confidence scoring (0.0-1.0) and lifecycle management (active/superseded/invalid)
- Memory API endpoints: POST/GET/PUT/DELETE /memory

Context builder integration (trust precedence per Master Plan):
  1. Trusted Project State (highest trust, 20% budget)
  2. Identity + Preference memories (10% budget)
  3. Retrieved chunks (remaining budget)

Also fixed database.py to use dynamic settings reference for test isolation.
45/45 tests passing.

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

src/atocore/api/routes.py

@@ -17,6 +17,14 @@ from atocore.context.project_state import (
     set_state,
 )
 from atocore.ingestion.pipeline import ingest_file, ingest_folder, get_ingestion_stats
+from atocore.memory.service import (
+    MEMORY_TYPES,
+    create_memory,
+    get_memories,
+    invalidate_memory,
+    supersede_memory,
+    update_memory,
+)
 from atocore.observability.logger import get_logger
 from atocore.retrieval.retriever import retrieve
 from atocore.retrieval.vector_store import get_vector_store
@@ -63,6 +71,19 @@ class ContextBuildResponse(BaseModel):
     chunks: list[dict]
 
 
+class MemoryCreateRequest(BaseModel):
+    memory_type: str
+    content: str
+    project: str = ""
+    confidence: float = 1.0
+
+
+class MemoryUpdateRequest(BaseModel):
+    content: str | None = None
+    confidence: float | None = None
+    status: str | None = None
+
+
 class ProjectStateSetRequest(BaseModel):
     project: str
     category: str
@@ -153,6 +174,77 @@ def api_build_context(req: ContextBuildRequest) -> ContextBuildResponse:
     )
 
 
+@router.post("/memory")
+def api_create_memory(req: MemoryCreateRequest) -> dict:
+    """Create a new memory entry."""
+    try:
+        mem = create_memory(
+            memory_type=req.memory_type,
+            content=req.content,
+            project=req.project,
+            confidence=req.confidence,
+        )
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    return {"status": "ok", "id": mem.id, "memory_type": mem.memory_type}
+
+
+@router.get("/memory")
+def api_get_memories(
+    memory_type: str | None = None,
+    active_only: bool = True,
+    min_confidence: float = 0.0,
+    limit: int = 50,
+) -> dict:
+    """List memories, optionally filtered."""
+    memories = get_memories(
+        memory_type=memory_type,
+        active_only=active_only,
+        min_confidence=min_confidence,
+        limit=limit,
+    )
+    return {
+        "memories": [
+            {
+                "id": m.id,
+                "memory_type": m.memory_type,
+                "content": m.content,
+                "confidence": m.confidence,
+                "status": m.status,
+                "updated_at": m.updated_at,
+            }
+            for m in memories
+        ],
+        "types": MEMORY_TYPES,
+    }
+
+
+@router.put("/memory/{memory_id}")
+def api_update_memory(memory_id: str, req: MemoryUpdateRequest) -> dict:
+    """Update an existing memory."""
+    try:
+        success = update_memory(
+            memory_id=memory_id,
+            content=req.content,
+            confidence=req.confidence,
+            status=req.status,
+        )
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    if not success:
+        raise HTTPException(status_code=404, detail="Memory not found")
+    return {"status": "updated", "id": memory_id}
+
+
+@router.delete("/memory/{memory_id}")
+def api_invalidate_memory(memory_id: str) -> dict:
+    """Invalidate a memory (error correction)."""
+    success = invalidate_memory(memory_id)
+    if not success:
+        raise HTTPException(status_code=404, detail="Memory not found")
+    return {"status": "invalidated", "id": memory_id}
+
+
 @router.post("/project/state")
 def api_set_project_state(req: ProjectStateSetRequest) -> dict:
     """Set or update a trusted project state entry."""