fix: resolve CI failures in VS Code extension PR

- Fix Windows MCP test failures: use pathToFileURL() instead of bare
  join() paths for dynamic imports, fixing ERR_UNSUPPORTED_ESM_URL_SCHEME
  on Windows where D:\ paths are not valid ESM import specifiers

- Remove parallel orchestration code that was WIP from another feature
  branch and not part of the VS Code extension scope (commands.ts,
  preferences.ts, types.ts changes reverted to main)

- Rebase cleanly onto main, resolving mcp-server.ts merge conflict by
  keeping main's dynamic import approach with PR's exported interface
  and JSDoc documentation

src/tests/mcp-server.test.ts

@@ -1,30 +1,37 @@
 import test from 'node:test'
 import assert from 'node:assert/strict'
 import { join } from 'node:path'
-import { fileURLToPath } from 'node:url'
+import { fileURLToPath, pathToFileURL } from 'node:url'
 
 const projectRoot = join(fileURLToPath(import.meta.url), '..', '..', '..')
 
+/**
+ * Resolve dist path as a file:// URL for cross-platform dynamic import.
+ * On Windows, bare paths like `D:\...\mcp-server.js` fail with
+ * ERR_UNSUPPORTED_ESM_URL_SCHEME because Node's ESM loader requires
+ * file:// URLs for absolute paths.
+ */
+function distUrl(filename: string): string {
+  return pathToFileURL(join(projectRoot, 'dist', filename)).href
+}
+
 test('mcp-server module imports without errors', async () => {
   // Import from the compiled dist output to avoid subpath resolution issues
   // that occur when the resolve-ts test hook rewrites .js -> .ts paths.
-  const distPath = join(projectRoot, 'dist', 'mcp-server.js')
-  const mod = await import(distPath)
+  const mod = await import(distUrl('mcp-server.js'))
   assert.ok(mod, 'module should be importable')
   assert.strictEqual(typeof mod.startMcpServer, 'function', 'startMcpServer should be a function')
 })
 
 test('startMcpServer accepts the correct argument shape', async () => {
-  const distPath = join(projectRoot, 'dist', 'mcp-server.js')
-  const { startMcpServer } = await import(distPath)
+  const { startMcpServer } = await import(distUrl('mcp-server.js'))
 
   assert.strictEqual(typeof startMcpServer, 'function')
   assert.strictEqual(startMcpServer.length, 1, 'startMcpServer should accept one argument')
 })
 
 test('startMcpServer can be called with mock tools', async () => {
-  const distPath = join(projectRoot, 'dist', 'mcp-server.js')
-  const { startMcpServer } = await import(distPath)
+  const { startMcpServer } = await import(distUrl('mcp-server.js'))
 
   // Create a mock tool matching the McpToolDef interface
   const mockTool = {