Add bulk editing to inventory tab with atomic batch API

Multi-select inventory items via checkboxes (select-all, shift-click
range, group header select) and apply bulk actions through a floating
toolbar: edit fields (shop, bin, price, THC/CBD), consume, checkout,
check in, and mark gone. Backend processes all operations in a single
SQLite transaction for atomicity.

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

web/src/api.ts

@@ -1,5 +1,12 @@
 import type { Bootstrap, AuditMode } from "./types.js";
 
+export type BatchOp =
+  | { action: "update"; id: string; fields: Partial<{ shopId: string | null; binId: string | null; price: number; thc: number; cbd: number; totalCannabinoids: number }> }
+  | { action: "checkout"; id: string; date: string }
+  | { action: "checkin"; id: string; date: string; binId: string }
+  | { action: "finish"; id: string; date: string; rating?: number; notes?: string }
+  | { action: "gone"; id: string; date: string; reason: string; notes?: string };
+
 async function request<T>(path: string, init?: RequestInit): Promise<T> {
   const res = await fetch(`/api${path}`, {
     ...init,
@@ -146,6 +153,12 @@ export const api = {
       body: JSON.stringify(body),
     }),
 
+  batchInventory: (ops: BatchOp[]) =>
+    request<{ ok: true; count: number }>("/inventory/batch", {
+      method: "POST",
+      body: JSON.stringify({ ops }),
+    }),
+
   // Catalog tables (brand/shop/bin) — unchanged
   createBrand: (name: string) =>
     request<{ id: string; name: string }>("/brands", {