feat: public text items, wall, and detail API

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/api/public.py

@@ -0,0 +1,50 @@
+from fastapi import APIRouter, Depends, HTTPException, Query, Request
+from sqlalchemy.orm import Session
+
+from app.db import get_db
+from app.schemas import ItemCreate, ItemOut, WallResponse
+from app.services import items as items_service
+
+router = APIRouter(prefix="/api/items", tags=["items"])
+
+
+def _client_ip(request: Request) -> str:
+    forwarded = request.headers.get("x-forwarded-for")
+    if forwarded:
+        return forwarded.split(",")[0].strip()
+    if request.client and request.client.host:
+        return request.client.host
+    return ""
+
+
+@router.post("", response_model=ItemOut)
+def create_item(
+    payload: ItemCreate,
+    request: Request,
+    db: Session = Depends(get_db),
+):
+    item = items_service.create_text_item(db, payload, _client_ip(request))
+    return items_service.item_to_dict(item)
+
+
+@router.get("/wall", response_model=WallResponse)
+def wall(
+    page: int = Query(1, ge=1),
+    page_size: int = Query(20, ge=1, le=100),
+    db: Session = Depends(get_db),
+):
+    rows, total = items_service.list_wall(db, page=page, page_size=page_size)
+    return WallResponse(
+        items=[ItemOut.model_validate(items_service.item_to_dict(i)) for i in rows],
+        page=page,
+        page_size=page_size,
+        total=total,
+    )
+
+
+@router.get("/{slug}", response_model=ItemOut)
+def get_item(slug: str, db: Session = Depends(get_db)):
+    item = items_service.get_item(db, slug)
+    if item is None:
+        raise HTTPException(status_code=404, detail="Not found")
+    return items_service.item_to_dict(item)