fix: add CJS build for NestJS CommonJS compatibility

NestJS compiles to CommonJS, but the package only exported ESM.
Node throws ERR_PACKAGE_PATH_NOT_EXPORTED when CJS code requires
an ESM-only package. Added dual ESM/CJS build with proper exports
conditions.

- ESM output in dist/esm/, CJS output in dist/cjs/
- package.json exports now includes import, require, and default
- Bumped to 0.1.1

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

package.json

@@ -1,14 +1,17 @@
 {
   "name": "@mosaicstack/telemetry-client",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "description": "TypeScript client SDK for Mosaic Stack Telemetry",
   "type": "module",
-  "main": "./dist/index.js",
+  "main": "./dist/cjs/index.js",
-  "types": "./dist/index.d.ts",
+  "module": "./dist/esm/index.js",
+  "types": "./dist/esm/index.d.ts",
   "exports": {
     ".": {
-      "types": "./dist/index.d.ts",
+      "types": "./dist/esm/index.d.ts",
-      "import": "./dist/index.js"
+      "import": "./dist/esm/index.js",
+      "require": "./dist/cjs/index.js",
+      "default": "./dist/esm/index.js"
     }
   },
   "engines": {
@@ -19,7 +22,7 @@
   ],
   "license": "MPL-2.0",
   "scripts": {
-    "build": "tsc -p tsconfig.build.json",
+    "build": "tsc -p tsconfig.build.json && tsc -p tsconfig.cjs.json && echo '{\"type\":\"commonjs\"}' > dist/cjs/package.json",
     "test": "vitest run",
     "test:watch": "vitest",
     "test:coverage": "vitest run --coverage",

tsconfig.build.json

@@ -1,4 +1,7 @@
 {
   "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "outDir": "./dist/esm"
+  },
   "exclude": ["node_modules", "dist", "tests", "**/*.test.ts"]
 }

tsconfig.cjs.json

@@ -0,0 +1,9 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "module": "CommonJS",
+    "moduleResolution": "node",
+    "outDir": "./dist/cjs"
+  },
+  "exclude": ["node_modules", "dist", "tests", "**/*.test.ts"]
+}