feat: v2.7.8 — Artifacts hub, clone related repos as extra folders, quieter resume prompt

- Artifacts (/artifacts): claude.ai pages sessions publish (captured from the
  Artifact tool's hook), pinned workspace files, skills and plugins, each
  kept as a snapshot; shared ones appear in a Hub and a skill or plugin
  installs into the viewer's own account (server/lib/artifacts.js,
  /api/artifacts, docs/plans/artifacts/).
- Workspace extra folders: clone one or more related repos beside the
  workspace and add them in one step (POST /api/lanes/:id/sources/clone).
- A pane that ended by itself while tmux kept running is no longer offered
  for resume (tmux.serverStartedAt in reconcileOrphans).
- Changes panel: a folder that is not a git repo opens on Files, and its
  files open from there.
- Plus the parallel sessions' work in this tree: File Explorer button in the
  panel header, user delete, RSA SSH keys, chat/terminal and pet fixes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

client/src/components/run/__tests__/PaneChat.test.tsx

@@ -434,6 +434,45 @@ describe("PaneChat — the unsent prompt", () => {
     await waitFor(() => expect(localStorage.getItem("agenthub.chat.draft.s1")).toBeNull());
   });
 
+  // A drag from outside the dashboard (a file manager, VS Code, a selection)
+  // carries only text: the terminal beneath pastes it, so the chat takes it too.
+  const textDrop = (data: Record<string, string>) => {
+    const drop = new Event("drop", { bubbles: true, cancelable: true });
+    Object.defineProperty(drop, "dataTransfer", {
+      value: { types: Object.keys(data), getData: (t: string) => data[t] ?? "", files: [] },
+    });
+    act(() => {
+      screen.getByTestId("pane-chat").dispatchEvent(drop);
+    });
+    return drop;
+  };
+
+  it("attaches the local files of a dropped file:// list", async () => {
+    renderChat();
+    const drop = textDrop({
+      "text/uri-list": "file:///home/u/My%20Docs/spec.md\r\nfile:///home/u/b.ts",
+      "text/plain": "/home/u/My Docs/spec.md",
+    });
+    expect(drop.defaultPrevented).toBe(true);
+    expect(await screen.findByText("spec.md")).toBeInTheDocument();
+    expect(screen.getByText("b.ts")).toBeInTheDocument();
+    fireEvent.change(screen.getByPlaceholderText("Write a message…"), {
+      target: { value: "read" },
+    });
+    fireEvent.click(screen.getByTestId("pane-chat-send"));
+    expect(submitToRun).toHaveBeenCalledWith(
+      "agenthub-lane-1",
+      'read @"/home/u/My Docs/spec.md" @/home/u/b.ts'
+    );
+  });
+
+  it("inserts dropped plain text into the prompt", () => {
+    renderChat();
+    const drop = textDrop({ "text/plain": "src/lib/x.ts" });
+    expect(drop.defaultPrevented).toBe(true);
+    expect(screen.getByPlaceholderText("Write a message…")).toHaveValue("src/lib/x.ts");
+  });
+
   // Issue #73: before the session starts the CLI may be asking in the terminal
   // (trust this folder? — "No, exit" preselected); an Enter sent from here
   // would answer it, so a send asks first.

client/src/components/run/__tests__/TerminalView.test.tsx

@@ -520,9 +520,15 @@ describe("TerminalView", () => {
       "application/x-agenthub-attach": '{"path":"@src/a.ts","name":"a.ts"}',
       "text/plain": "src/a.ts",
     };
-    const dataTransfer = { types: Object.keys(data), files: [], getData: (k: string) => data[k] ?? "" };
+    const dataTransfer = {
+      types: Object.keys(data),
+      files: [],
+      getData: (k: string) => data[k] ?? "",
+    };
     fireEvent.dragEnter(screen.getByTestId("terminal-view"), { dataTransfer });
-    expect(screen.getByTestId("terminal-drop")).toHaveTextContent("Drop to paste into the terminal");
+    expect(screen.getByTestId("terminal-drop")).toHaveTextContent(
+      "Drop to paste into the terminal"
+    );
     fireEvent.drop(screen.getByTestId("terminal-view"), { dataTransfer });
     expect(pasteMock).toHaveBeenCalledWith("src/a.ts ");
     expect(screen.queryByTestId("terminal-drop")).toBeNull();
@@ -582,6 +588,24 @@ describe("TerminalView", () => {
     vi.useRealTimers();
   });
 
+  // ^Z suspended claude: the pane fell to its shell and the session looked
+  // closed. Ctrl+Z is undo in a browser, so it sends Ctrl+_ instead.
+  it("turns Ctrl+Z into undo (Ctrl+_) and never sends ^Z, which would suspend the session", () => {
+    inputMock.mockClear();
+    render(<TerminalView runId="r1" wsBaseUrl="ws://x" />);
+    const handler = keyHandlerMock.mock.calls[0]![0]! as (e: KeyboardEvent) => boolean;
+    const ev = new KeyboardEvent("keydown", { key: "z", ctrlKey: true, cancelable: true });
+    expect(handler(ev)).toBe(false);
+    expect(ev.defaultPrevented).toBe(true);
+    expect(inputMock).toHaveBeenCalledWith("\x1f", true);
+    expect(inputMock).not.toHaveBeenCalledWith("\x1a", expect.anything());
+    // Other chords with Z are left to xterm (Ctrl+Shift+Z, plain z).
+    expect(handler(new KeyboardEvent("keydown", { key: "Z", ctrlKey: true, shiftKey: true }))).toBe(
+      true
+    );
+    expect(handler(new KeyboardEvent("keydown", { key: "z" }))).toBe(true);
+  });
+
   // Safari + macOS's own Vietnamese Telex: the first letter is an insertText,
   // every later key REPLACES the word — the event order captured on a Mac.
   it("forwards Safari Telex's word replacements as backspaces plus the new tail", () => {