Initial commit: CI Agent competitive-intelligence monitoring app

FastAPI + Celery + Next.js + Postgres/Redis app with company monitoring,
source collection, LLM-based change analysis, enrichment, and account
security (Turnstile, escalating lockout, email verification).

apps/api/app/repositories/detected_change_repository.py

@@ -0,0 +1,51 @@
+from __future__ import annotations
+
+import uuid
+from datetime import datetime
+from typing import Any
+
+from sqlalchemy import select
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from app.models.detected_change import DetectedChange
+from app.models.enums import ChangeType
+
+
+class DetectedChangeRepository:
+    def __init__(self, db: AsyncSession) -> None:
+        self.db = db
+
+    async def get_recent_for_source_and_type(
+        self, source_id: uuid.UUID, change_type: ChangeType, since: datetime
+    ) -> DetectedChange | None:
+        """Most recent DetectedChange of this type for this source within
+        the cooldown window - used both to flag repeats (lower significance)
+        and to suppress exact duplicates (see change_detection_service.py)."""
+        result = await self.db.execute(
+            select(DetectedChange)
+            .where(
+                DetectedChange.source_id == source_id,
+                DetectedChange.change_type == change_type,
+                DetectedChange.created_at >= since,
+            )
+            .order_by(DetectedChange.created_at.desc())
+            .limit(1)
+        )
+        return result.scalar_one_or_none()
+
+    async def create(self, **kwargs: Any) -> DetectedChange:
+        change = DetectedChange(**kwargs)
+        self.db.add(change)
+        await self.db.flush()
+        return change
+
+    async def list_for_company(
+        self, company_id: uuid.UUID, limit: int = 100
+    ) -> list[DetectedChange]:
+        result = await self.db.execute(
+            select(DetectedChange)
+            .where(DetectedChange.company_id == company_id)
+            .order_by(DetectedChange.created_at.desc())
+            .limit(limit)
+        )
+        return list(result.scalars().all())