Add Reddit monitoring bot — backend, frontend, and Docker config

Python/FastAPI backend with PostgreSQL for collecting Reddit data via
public .json endpoints. React/Vite dashboard for analytics. Docker Compose
setup with API and worker services connecting to shared PostgreSQL.

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

backend/services/subreddit_service.py

@@ -0,0 +1,75 @@
+from sqlalchemy import select, func
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from backend.models.subreddit import MonitoredSubreddit
+from backend.models.post import Post
+
+
+async def list_subreddits(db: AsyncSession) -> list[dict]:
+    stmt = (
+        select(
+            MonitoredSubreddit,
+            func.count(Post.id).label("post_count"),
+        )
+        .outerjoin(Post, Post.subreddit_id == MonitoredSubreddit.id)
+        .group_by(MonitoredSubreddit.id)
+        .order_by(MonitoredSubreddit.name)
+    )
+    result = await db.execute(stmt)
+    rows = result.all()
+    out = []
+    for sub, post_count in rows:
+        data = {c.name: getattr(sub, c.name) for c in sub.__table__.columns}
+        data["post_count"] = post_count
+        out.append(data)
+    return out
+
+
+async def get_subreddit(db: AsyncSession, subreddit_id: int) -> dict | None:
+    stmt = (
+        select(
+            MonitoredSubreddit,
+            func.count(Post.id).label("post_count"),
+        )
+        .outerjoin(Post, Post.subreddit_id == MonitoredSubreddit.id)
+        .where(MonitoredSubreddit.id == subreddit_id)
+        .group_by(MonitoredSubreddit.id)
+    )
+    result = await db.execute(stmt)
+    row = result.first()
+    if not row:
+        return None
+    sub, post_count = row
+    data = {c.name: getattr(sub, c.name) for c in sub.__table__.columns}
+    data["post_count"] = post_count
+    return data
+
+
+async def create_subreddit(db: AsyncSession, name: str) -> MonitoredSubreddit:
+    sub = MonitoredSubreddit(name=name.lower().strip())
+    db.add(sub)
+    await db.commit()
+    await db.refresh(sub)
+    return sub
+
+
+async def update_subreddit(
+    db: AsyncSession, subreddit_id: int, is_active: bool | None = None
+) -> MonitoredSubreddit | None:
+    sub = await db.get(MonitoredSubreddit, subreddit_id)
+    if not sub:
+        return None
+    if is_active is not None:
+        sub.is_active = is_active
+    await db.commit()
+    await db.refresh(sub)
+    return sub
+
+
+async def delete_subreddit(db: AsyncSession, subreddit_id: int) -> bool:
+    sub = await db.get(MonitoredSubreddit, subreddit_id)
+    if not sub:
+        return False
+    sub.is_active = False
+    await db.commit()
+    return True