feat(chat): terminal chat parity for every tool; Desktop-like artifacts

- The chat over a terminal pane now covers Claude, Codex, omp, Cursor and
  Antigravity: Cursor's agent transcript and agy's step log
  (brain/<id>/.system_generated/logs/transcript_full.jsonl) are read as
  conversations; Cursor sessions are claimed by their workspace
- Replies appear as soon as they are written: the projects-tree watcher
  broadcasts `transcript_changed` (at most every 250 ms per session) and the
  chat re-reads the transcript while the terminal underneath draws
- Stop shows from the pane's own busy line (Claude/Codex `esc to interrupt`,
  agy `… esc to cancel`), or fresh output for omp/Cursor — no hooks needed
- Permission prompts read off the terminal become a card with the tool, its
  command and "Deny with a note"; Codex gets Permission mode / Model buttons
  that open its own numbered pickers, answered from the menu card
- Artifacts: cards for pages/documents/diagrams/tables/React components, a
  Preview | Code panel with versions, copy, download, save to the Artifacts
  Hub, full screen; sandboxed iframes without allow-same-origin
- Claude panes get CLAUDE_CODE_ENABLE_TODO_TOOLS=1 so the Progress panel has a
  plan; multi-question pane menus read their Next row and question tabs
- The realtime chat bridge (structured stdio, /api/chat-bridge, /ws-chat)
  from the unreleased ad9d475 is not kept

client/src/lib/__tests__/artifactView.test.ts

@@ -0,0 +1,102 @@
+/**
+ * @file artifactView.test.ts
+ * @description What counts as an artifact and how it is shown: kinds by
+ * name, a React file only when written whole, a file's versions rebuilt from
+ * the conversation's Write/Edit/MultiEdit inputs (a failed call skipped, an
+ * edit to unseen text unknown), CSV rows, and the sandboxed documents.
+ * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
+ */
+
+import { describe, expect, it } from "vitest";
+import {
+  artifactDocument,
+  artifactKind,
+  artifactVersions,
+  frameSandbox,
+  isArtifact,
+  parseCsv,
+} from "../artifactView";
+import type { TranscriptMessage } from "../types";
+
+const use = (id: string, name: string, input: Record<string, unknown>): TranscriptMessage => ({
+  type: "assistant",
+  timestamp: `2026-10-21T00:00:0${id}.000Z`,
+  content: [{ type: "tool_use", id, name, input } as TranscriptMessage["content"][number]],
+});
+const result = (id: string, isError = false): TranscriptMessage => ({
+  type: "user",
+  sender: "tool",
+  timestamp: null,
+  content: [
+    {
+      type: "tool_result",
+      id,
+      output: "",
+      is_error: isError,
+    } as TranscriptMessage["content"][number],
+  ],
+});
+
+describe("artifactView", () => {
+  it("knows an artifact by its name", () => {
+    expect(artifactKind("/a/page.HTML")).toBe("html");
+    expect(artifactKind("d.mmd")).toBe("mermaid");
+    expect(artifactKind("App.tsx")).toBe("react");
+    expect(artifactKind("x.go")).toBe("code");
+    expect(isArtifact("report.md", false)).toBe(true);
+    expect(isArtifact("App.tsx", false)).toBe(false);
+    expect(isArtifact("App.tsx", true)).toBe(true);
+    expect(isArtifact("server.js", true)).toBe(false);
+  });
+
+  it("rebuilds a file's versions from Write, Edit and MultiEdit", () => {
+    const msgs = [
+      use("1", "Write", { file_path: "/w/a.md", content: "# A\nold line\n" }),
+      result("1"),
+      use("2", "Edit", { file_path: "/w/a.md", old_string: "old", new_string: "new" }),
+      result("2"),
+      use("3", "Edit", { file_path: "/w/a.md", old_string: "missing", new_string: "x" }),
+      result("3", true),
+      use("4", "MultiEdit", {
+        file_path: "/w/a.md",
+        edits: [{ old_string: "# A", new_string: "# B" }],
+      }),
+      result("4"),
+      use("5", "Write", { file_path: "/w/other.md", content: "no" }),
+    ];
+    const v = artifactVersions(msgs, "/w/a.md");
+    expect(v.map((x) => x.content)).toEqual([
+      "# A\nold line\n",
+      "# A\nnew line\n",
+      "# B\nnew line\n",
+    ]);
+  });
+
+  it("says an edit to text it never saw is of unknown content", () => {
+    const v = artifactVersions(
+      [use("1", "Edit", { file_path: "a.md", old_string: "a", new_string: "b" })],
+      "a.md"
+    );
+    expect(v).toHaveLength(1);
+    expect(v[0]!.content).toBeNull();
+  });
+
+  it("reads CSV with quotes and newlines inside them", () => {
+    expect(parseCsv('a,b\n"x, y","say ""hi""\nthere"\n')).toEqual([
+      ["a", "b"],
+      ["x, y", 'say "hi"\nthere'],
+    ]);
+  });
+
+  it("builds sandboxed documents that keep the source inert inside a script", () => {
+    const doc = artifactDocument("react", "export default () => <p>a</script>b</p>", false)!;
+    expect(doc).toContain("babel");
+    expect(doc).not.toContain("a</script>b");
+    expect(artifactDocument("mermaid", "graph TD; A-->B<img>", true)).toContain(
+      "A--&gt;B&lt;img&gt;"
+    );
+    expect(artifactDocument("code", "x", false)).toBeNull();
+    expect(frameSandbox("svg")).toBe("");
+    expect(frameSandbox("html")).not.toContain("allow-same-origin");
+  });
+});