feat!: replace bundled pnpm binary with npm + lockfile bootstrap

Remove the 9MB bundled pnpm.cjs/worker.js and instead use npm ci with
committed package-lock.json files (~5KB) to install a bootstrap pnpm,
which then installs the target version with integrity verification via
the project's pnpm-lock.yaml.

Also switch from ncc to esbuild and modernize to ESM.

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

tsconfig.json

@@ -1,26 +1,19 @@
-
 {
   "compilerOptions": {
     "target": "ES2022",
-    "module": "Node16",
+    "module": "ESNext",
+    "moduleResolution": "bundler",
     "resolveJsonModule": true,
     "lib": [
       "ES2023"
     ],
-    "outDir": "./dist/tsc",
-    "preserveConstEnums": true,
-    "incremental": false,
-    "declaration": true,
-    "sourceMap": true,
-    "importHelpers": false,
+    "noEmit": true,
     "strict": true,
     "pretty": true,
     "noUnusedLocals": true,
     "noUnusedParameters": true,
     "noImplicitReturns": true,
     "noFallthroughCasesInSwitch": true,
-    "esModuleInterop": true,
-    "experimentalDecorators": true,
-    "emitDecoratorMetadata": true
+    "esModuleInterop": true
   }
 }