Eliminate hardcoded idb version duplication with build-time code generation

The idb version was hardcoded in both package.json and the CDN import URL.
Add a prebuild script that reads the version from package.json and generates
a TypeScript constant, so the version is defined in one place only.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: robertmclaws

src/CloudNimble.BlazorEssentials.IndexedDb/Scripts/generate-idb-version.js

@@ -0,0 +1,15 @@
+const fs = require('fs');
+const path = require('path');
+
+const packageJson = JSON.parse(fs.readFileSync(path.join(__dirname, '..', 'package.json'), 'utf8'));
+const idbVersion = packageJson.dependencies.idb;
+
+const outputDir = path.join(__dirname, 'generated');
+if (!fs.existsSync(outputDir)) {
+    fs.mkdirSync(outputDir, { recursive: true });
+}
+
+const content = `// AUTO-GENERATED from package.json - DO NOT EDIT\nexport const IDB_VERSION = "${idbVersion}";\n`;
+
+fs.writeFileSync(path.join(outputDir, 'idb-version.ts'), content);
+console.log(`Generated idb-version.ts with version ${idbVersion}`);

src/CloudNimble.BlazorEssentials.IndexedDb/Scripts/generated/idb-version.ts

@@ -0,0 +1,2 @@
+// AUTO-GENERATED from package.json - DO NOT EDIT
+export const IDB_VERSION = "8.0.3";

src/CloudNimble.BlazorEssentials.IndexedDb/Scripts/idb-loader.ts

@@ -1,3 +1,5 @@
+import { IDB_VERSION } from './generated/idb-version';
+
 let idbModule: any = null;
 let isLoading = false;
 let loadPromise: Promise<any> | null = null;
@@ -34,7 +36,7 @@ async function loadIdbWithFallback() {
     try {
         // Try online CDN first
         // @ts-ignore - Dynamic import from CDN
-        const onlineModule = await import('https://cdn.jsdelivr.net/npm/idb@8.0.3/+esm');
+        const onlineModule = await import(`https://cdn.jsdelivr.net/npm/idb@${IDB_VERSION}/+esm`);
         console.log('Loaded idb from online CDN');
         return onlineModule;
     } catch (onlineError) {

src/CloudNimble.BlazorEssentials.IndexedDb/package.json

@@ -7,9 +7,10 @@
   "author": "CloudNimble, Inc.",
   "license": "ISC",
   "scripts": {
+    "prebuild": "node Scripts/generate-idb-version.js",
     "build": "tsc",
     "watch": "tsc --watch",
-    "clean": "rimraf wwwroot/*.js wwwroot/*.js.map"
+    "clean": "rimraf wwwroot/*.js wwwroot/*.js.map Scripts/generated"
   },
   "devDependencies": {
     "@microsoft/dotnet-js-interop": "10.0.0",