feat(19-02): add catalog-linked candidates, branched resolution, remove link/unlink routes

- getThreadWithCandidates LEFT JOINs globalItems with COALESCE for name, weight, price, image
- createCandidate accepts and stores globalItemId
- resolveThread branches: reference item (globalItemId set) vs standalone (full data copy)
- Removed link/unlink endpoints from items route (replaced by direct globalItemId FK)
- 6 new tests for catalog-linked candidates and branched resolution

src/server/routes/items.ts

@@ -1,16 +1,8 @@
 import { zValidator } from "@hono/zod-validator";
 import { Hono } from "hono";
-import {
-	createItemSchema,
-	linkItemSchema,
-	updateItemSchema,
-} from "../../shared/schemas.ts";
+import { createItemSchema, updateItemSchema } from "../../shared/schemas.ts";
 import { parseId } from "../lib/params.ts";
 import { exportItemsCsv, importItemsCsv } from "../services/csv.service.ts";
-import {
-	linkItemToGlobal,
-	unlinkItemFromGlobal,
-} from "../services/global-item.service.ts";
 import {
 	createItem,
 	deleteItem,
@@ -122,32 +114,5 @@ app.delete("/:id", async (c) => {
 	return c.json({ success: true });
 });
 
-app.post("/:id/link", zValidator("json", linkItemSchema), (c) => {
-	const db = c.get("db");
-	const id = parseId(c.req.param("id"));
-	if (!id) return c.json({ error: "Invalid item ID" }, 400);
-
-	const item = getItemById(db, id);
-	if (!item) return c.json({ error: "Item not found" }, 404);
-
-	try {
-		const link = linkItemToGlobal(db, id, c.req.valid("json").globalItemId);
-		return c.json(link, 201);
-	} catch {
-		return c.json({ error: "Item already linked to a global item" }, 409);
-	}
-});
-
-app.delete("/:id/link", (c) => {
-	const db = c.get("db");
-	const id = parseId(c.req.param("id"));
-	if (!id) return c.json({ error: "Invalid item ID" }, 400);
-
-	const item = getItemById(db, id);
-	if (!item) return c.json({ error: "Item not found" }, 404);
-
-	unlinkItemFromGlobal(db, id);
-	return c.json({ success: true });
-});
 
 export { app as itemRoutes };