feat: add @automaker/model-resolver package

- Extract model string resolution logic
- Map model aliases to full model strings (haiku -> claude-haiku-4-5)
- Handle multiple model sources with priority
- Re-export model constants from @automaker/types

Provides centralized model resolution for Claude models.
Simplifies model handling across server and UI.

Dependencies: @automaker/types

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

libs/model-resolver/tsconfig.json

@@ -0,0 +1,20 @@
+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "module": "commonjs",
+    "lib": ["ES2020"],
+    "types": ["node"],
+    "declaration": true,
+    "declarationMap": true,
+    "outDir": "./dist",
+    "rootDir": "./src",
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "resolveJsonModule": true,
+    "moduleResolution": "node"
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist"]
+}