test(18-02): add failing tests for global item service and seed

- 10 test cases covering search, owner count, link/unlink, seed idempotency
- Added globalItems/itemGlobalLinks tables to SQLite schema
- Added Zod schemas and types for global items
- Created 18-item bikepacking gear seed data JSON

drizzle/0010_demonic_rawhide_kid.sql

@@ -0,0 +1,21 @@
+CREATE TABLE `global_items` (
+	`id` integer PRIMARY KEY AUTOINCREMENT NOT NULL,
+	`brand` text NOT NULL,
+	`model` text NOT NULL,
+	`category` text,
+	`weight_grams` real,
+	`price_cents` integer,
+	`image_url` text,
+	`description` text,
+	`created_at` integer NOT NULL
+);
+--> statement-breakpoint
+CREATE TABLE `item_global_links` (
+	`id` integer PRIMARY KEY AUTOINCREMENT NOT NULL,
+	`item_id` integer NOT NULL,
+	`global_item_id` integer NOT NULL,
+	FOREIGN KEY (`item_id`) REFERENCES `items`(`id`) ON UPDATE no action ON DELETE cascade,
+	FOREIGN KEY (`global_item_id`) REFERENCES `global_items`(`id`) ON UPDATE no action ON DELETE cascade
+);
+--> statement-breakpoint
+CREATE UNIQUE INDEX `item_global_links_item_id_unique` ON `item_global_links` (`item_id`);

drizzle/meta/_journal.json

@@ -71,6 +71,13 @@
       "when": 1775287060443,
       "tag": "0009_happy_mockingbird",
       "breakpoints": true
+    },
+    {
+      "idx": 10,
+      "version": "6",
+      "when": 1775387093955,
+      "tag": "0010_demonic_rawhide_kid",
+      "breakpoints": true
     }
   ]
 }