feat: TypeScript telemetry client SDK v0.1.0

Standalone npm package (@mosaicstack/telemetry-client) for reporting
task-completion telemetry and querying predictions from the Mosaic
Stack Telemetry server.

- TelemetryClient with setInterval-based background flush
- EventQueue (bounded FIFO array)
- BatchSubmitter with native fetch, exponential backoff, Retry-After
- PredictionCache (Map + TTL)
- EventBuilder with auto-generated event_id/timestamp
- Zero runtime dependencies (Node 18+ native APIs)
- 43 tests, 86% branch coverage

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

eslint.config.js

@@ -0,0 +1,25 @@
+import eslint from '@eslint/js';
+import tseslint from '@typescript-eslint/eslint-plugin';
+import tsparser from '@typescript-eslint/parser';
+
+export default [
+  eslint.configs.recommended,
+  {
+    files: ['src/**/*.ts', 'tests/**/*.ts'],
+    languageOptions: {
+      parser: tsparser,
+      parserOptions: {
+        ecmaVersion: 2022,
+        sourceType: 'module',
+      },
+    },
+    plugins: {
+      '@typescript-eslint': tseslint,
+    },
+    rules: {
+      ...tseslint.configs.recommended.rules,
+      'no-unused-vars': 'off',
+      '@typescript-eslint/no-unused-vars': ['error', { argsIgnorePattern: '^_' }],
+    },
+  },
+];