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.

e2e-tests/chat_search.spec.ts

@@ -0,0 +1,126 @@
+import { test } from "./helpers/test_helper";
+
+test.skip("chat search - basic search dialog functionality", async ({ po }) => {
+  await po.setUp({ autoApprove: true });
+  await po.importApp("minimal");
+
+  // Create some chats with specific names for testing
+  await po.sendPrompt("[dump] create a todo application");
+  await po.waitForChatCompletion();
+
+  await po.clickNewChat();
+  await po.sendPrompt("[dump] build a weather dashboard");
+  await po.waitForChatCompletion();
+
+  await po.clickNewChat();
+  await po.sendPrompt("[dump] create a blog system");
+  await po.waitForChatCompletion();
+
+  // Test 1: Open search dialog using the search button
+  await po.page.getByTestId("search-chats-button").click();
+
+  // Wait for search dialog to appear
+  await po.page.getByTestId("chat-search-dialog").waitFor();
+
+  // Test 2: Close dialog with escape key
+  await po.page.keyboard.press("Escape");
+  await po.page.getByTestId("chat-search-dialog").waitFor({ state: "hidden" });
+
+  // Test 3: Open dialog again and verify it shows chats
+  await po.page.getByTestId("search-chats-button").click();
+  await po.page.getByTestId("chat-search-dialog").waitFor();
+
+  // Test 4: Search for specific term
+  await po.page.getByPlaceholder("Search chats").fill("todo");
+
+  // Wait a moment for search results
+  await po.page.waitForTimeout(500);
+
+  // Test 5: Clear search and close
+  await po.page.getByPlaceholder("Search chats").clear();
+  await po.page.keyboard.press("Escape");
+});
+
+test.skip("chat search - with named chats for easier testing", async ({
+  po,
+}) => {
+  await po.setUp({ autoApprove: true });
+  await po.importApp("minimal");
+
+  // Create chats with descriptive names that will be useful for testing
+  await po.sendPrompt("[dump] hello world app");
+  await po.waitForChatCompletion();
+
+  // Use a timeout to ensure the UI has updated before trying to interact
+  await po.page.waitForTimeout(1000);
+
+  await po.clickNewChat();
+  await po.sendPrompt("[dump] todo list manager");
+  await po.waitForChatCompletion();
+
+  await po.page.waitForTimeout(1000);
+
+  await po.clickNewChat();
+  await po.sendPrompt("[dump] weather forecast widget");
+  await po.waitForChatCompletion();
+
+  await po.page.waitForTimeout(1000);
+
+  // Test search functionality
+  await po.page.getByTestId("search-chats-button").click();
+  await po.page.getByTestId("chat-search-dialog").waitFor();
+
+  // Search for "todo" - should find the todo list manager chat
+  await po.page.getByPlaceholder("Search chats").fill("todo");
+  await po.page.waitForTimeout(500);
+
+  // Search for "weather" - should find the weather forecast widget chat
+  await po.page.getByPlaceholder("Search chats").fill("weather");
+  await po.page.waitForTimeout(500);
+
+  // Search for non-existent term
+  await po.page.getByPlaceholder("Search chats").fill("nonexistent");
+  await po.page.waitForTimeout(500);
+
+  await po.page.keyboard.press("Escape");
+});
+
+test.skip("chat search - keyboard shortcut functionality", async ({ po }) => {
+  await po.setUp({ autoApprove: true });
+  await po.importApp("minimal");
+
+  // Create a chat
+  await po.sendPrompt("[dump] sample app");
+  await po.waitForChatCompletion();
+
+  // Test keyboard shortcut (Ctrl+K)
+  await po.page.keyboard.press("Control+k");
+  await po.page.getByTestId("chat-search-dialog").waitFor();
+
+  // Close with escape
+  await po.page.keyboard.press("Escape");
+  await po.page.getByTestId("chat-search-dialog").waitFor({ state: "hidden" });
+});
+
+test.skip("chat search - navigation and selection", async ({ po }) => {
+  await po.setUp({ autoApprove: true });
+  await po.importApp("minimal");
+
+  // Create multiple chats
+  await po.sendPrompt("[dump] first application");
+  await po.waitForChatCompletion();
+
+  await po.clickNewChat();
+  await po.sendPrompt("[dump] second application");
+  await po.waitForChatCompletion();
+
+  // Test selecting a chat through search
+  await po.page.getByTestId("search-chats-button").click();
+  await po.page.getByTestId("chat-search-dialog").waitFor();
+
+  // Select the first chat item (assuming it shows "Untitled Chat" as default title)
+  await po.page.getByText("Untitled Chat").first().click();
+
+  // Dialog should close
+  await po.page.getByTestId("chat-search-dialog").waitFor({ state: "hidden" });
+});