Edit workspace files directly on web (#2270)

* feat(files): edit workspace files on web

Keep source buffers synchronized with host file changes and require an explicit overwrite or reload when revisions diverge.

* feat(panels): surface and protect modified tabs

Expose tooltip and modification state through the generic panel boundary so tabs can show stable metadata and guard every close route consistently.

* fix(tests): use portable fake timeout handle

* fix(files): harden editor conflict handling

Preserve modified panel state across tab eviction, use precise revisions for optimistic writes, coalesce concurrent file watchers, and localize the editor interface.

* fix(files): close editor concurrency gaps

Coalesce clean reloads, preserve subscriber identities and file permissions, suspend pending saves during close confirmation, and carry precise revisions through file reads.

* test(files): expect read revision metadata

packages/highlight/src/__tests__/parsers.test.ts

@@ -1,5 +1,10 @@
 import { describe, it, expect } from "vitest";
-import { isLanguageSupported, getSupportedExtensions, getParserForFile } from "../parsers.js";
+import {
+  isLanguageSupported,
+  getSupportedExtensions,
+  getParserForFile,
+  getLanguageForFile,
+} from "../parsers.js";
 
 describe("isLanguageSupported", () => {
   it("returns true for supported file extensions", () => {
@@ -60,6 +65,13 @@ describe("getSupportedExtensions", () => {
 });
 
 describe("getParserForFile", () => {
+  it("projects the parser retained by the editor language registry", () => {
+    for (const extension of getSupportedExtensions()) {
+      const filename = `source.${extension}`;
+      expect(getParserForFile(filename)).toBe(getLanguageForFile(filename)?.parser);
+    }
+  });
+
   it("returns a parser for supported files", () => {
     expect(getParserForFile("test.js")).not.toBeNull();
     expect(getParserForFile("test.py")).not.toBeNull();