Extract emails into separate package with clean interface

- Create packages/emails/ with EmailClient interface abstraction
- Wrap Postmark ServerClient in adapter for clean typing
- Add createLoggingEmailClient for dev mode (logs to console)
- Split email templates into individual files with full test coverage
- Update api-server to use new package via context injection
- Remove EMAIL_DEV_MODE - now uses POSTMARK_API_KEY presence
- Delete apps/api-server/src/utils/email.ts

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

packages/emails/package.json

@@ -0,0 +1,33 @@
+{
+  "name": "@reviq/emails",
+  "version": "0.0.1",
+  "private": true,
+  "type": "module",
+  "main": "./dist/index.js",
+  "types": "./dist/index.d.ts",
+  "exports": {
+    ".": {
+      "types": "./dist/index.d.ts",
+      "import": "./dist/index.js"
+    }
+  },
+  "scripts": {
+    "build": "tsc",
+    "clean": "tsc --build --clean && rm -rf dist/ node_modules/ .eslintcache",
+    "lint": "eslint . --cache",
+    "test": "bun test src/",
+    "test:cov": "bun test --coverage src/"
+  },
+  "dependencies": {
+    "@formatjs/intl-durationformat": "^0.7.0",
+    "@reviq/db-schema": "workspace:*",
+    "postmark": "^4.0.5"
+  },
+  "devDependencies": {
+    "@macalinao/eslint-config": "catalog:",
+    "@macalinao/tsconfig": "catalog:",
+    "@types/bun": "catalog:",
+    "eslint": "catalog:",
+    "typescript": "catalog:"
+  }
+}