feat: implement fuzzy search and replace functionality with Levenshtein distance

- Added `applySearchReplace` function to handle search and replace operations with fuzzy matching capabilities.
- Introduced tests for various scenarios including fuzzy matching with typos, exact matches, and handling whitespace differences.
- Created a parser for search/replace blocks to facilitate the new functionality.
- Updated prompts for search-replace operations to clarify usage and examples.
- Added utility functions for text normalization and language detection based on file extensions.
- Implemented a minimal stdio MCP server for local testing with tools for adding numbers and printing environment variables.

playwright.config.ts

@@ -7,7 +7,7 @@ const config: PlaywrightTestConfig = {
   testDir: "./e2e-tests",
   workers: 1,
   retries: process.env.CI ? 2 : 0,
-  timeout: process.env.CI ? 180_000 : 30_000,
+  timeout: process.env.CI ? 180_000 : 45_000,
   // Use a custom snapshot path template because Playwright's default
   // is platform-specific which isn't necessary for Dyad e2e tests
   // which should be platform agnostic (we don't do screenshots; only textual diffs).
@@ -42,10 +42,12 @@ const config: PlaywrightTestConfig = {
     // video: "retain-on-failure",
   },
 
-  webServer: {
-    command: `cd testing/fake-llm-server && npm run build && npm start`,
-    url: "http://localhost:3500/health",
-  },
+  webServer: [
+    {
+      command: `cd testing/fake-llm-server && npm run build && npm start`,
+      url: "http://localhost:3500/health",
+    },
+  ],
 };
 
 export default config;