feat(search): add @tower/search package with Meilisearch client and helpers

Implements Task 2 of Plan 4 (Archive & Search): provides createMeiliClient,
configureIndex, indexMessage, and deleteMessage for use by the worker and API.

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

packages/search/package.json

@@ -0,0 +1,27 @@
+{
+  "name": "@tower/search",
+  "version": "0.0.1",
+  "main": "./dist/index.js",
+  "types": "./dist/index.d.ts",
+  "exports": {
+    ".": {
+      "types": "./dist/index.d.ts",
+      "default": "./dist/index.js"
+    }
+  },
+  "scripts": {
+    "build": "tsc",
+    "dev": "tsc --watch",
+    "test": "jest"
+  },
+  "dependencies": {
+    "meilisearch": "^0.44.0"
+  },
+  "devDependencies": {
+    "@types/jest": "^29.0.0",
+    "@types/node": "^22.0.0",
+    "jest": "^29.0.0",
+    "ts-jest": "^29.0.0",
+    "typescript": "^5.7.0"
+  }
+}