feat: right-click menus in Files/Users/Artifacts; several SSH keys and accounts per host

- Files: right-click a sidebar workspace (Open, Copy path) or home (Open,
  Open Trash), a path crumb (Open, Download as zip, Paste into, Copy path),
  a Trash row (Restore, Copy path, Delete forever), the Trash area (Refresh,
  Empty Trash) and an admin's per-user Trash folder (Open, Empty Trash).
- Users: row menu (Edit + Open home in Files for an admin, Copy username/email).
- Artifacts: card menu repeating its buttons, plus Copy link for a page.
- Git identity: named SSH keys beside the default ones (id_<type>_<name>,
  max 10, DELETE ?id=); SSH logins per alias (`ssh://<alias>/` →
  `ssh://<user>@<host>/`, so several AWS CodeCommit accounts share a host),
  each optionally tied to one key (`agenthub.<from>.sshKey`) — a clone of
  that URL offers only that key and persists it. Terminal sshCommand follows
  the keys. Settings → Git: "More SSH keys" + account name/key in the AWS and
  other-host forms. Docs/API.md, OpenAPI updated.

client/src/pages/__tests__/Artifacts.test.tsx

@@ -6,10 +6,11 @@
  * a plugin is picked from the list its marketplace link answers (a link the
  * server cannot read opens the by-hand form), a skill is uploaded from one
  * Markdown file under the name the user types, or written in the dialog.
+ * A card's right-click menu runs the same actions (Preview, Delete).
  * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
  */
 import { describe, it, expect, vi, beforeEach } from "vitest";
-import { render, screen, waitFor, within } from "@testing-library/react";
+import { fireEvent, render, screen, waitFor, within } from "@testing-library/react";
 import userEvent from "@testing-library/user-event";
 import { MemoryRouter } from "react-router-dom";
 import { Artifacts } from "../Artifacts";
@@ -81,7 +82,13 @@ beforeEach(() => {
   vi.mocked(api.artifacts.list).mockResolvedValue({
     items: [
       item({}),
-      item({ id: 2, kind: "skill", title: "deploy", source: "deploy", files: [{ path: "SKILL.md", size: 3 }] }),
+      item({
+        id: 2,
+        kind: "skill",
+        title: "deploy",
+        source: "deploy",
+        files: [{ path: "SKILL.md", size: 3 }],
+      }),
     ],
   });
   vi.mocked(confirmDialog).mockReset();
@@ -145,7 +152,9 @@ describe("Adding", () => {
     await addMenu(user, "Skill");
     const md = new File(["# Steps"], "notes.md", { type: "text/markdown" });
     await user.upload(screen.getByTestId("skill-files"), md);
-    expect(await screen.findByTestId("skill-shape")).toHaveTextContent("becomes the skill's SKILL.md");
+    expect(await screen.findByTestId("skill-shape")).toHaveTextContent(
+      "becomes the skill's SKILL.md"
+    );
     const name = screen.getByLabelText(/Skill name/);
     await waitFor(() => expect(name).toHaveValue("notes"));
     await user.clear(name);
@@ -229,4 +238,19 @@ describe("Artifacts", () => {
     expect(frame.getAttribute("sandbox")).toBe("");
     expect(frame.getAttribute("src")).toBe("/api/artifacts/1/raw?path=report.html");
   });
+
+  it("opens a card's actions on right-click", async () => {
+    const user = userEvent.setup();
+    open();
+    await screen.findByText("report.html");
+    fireEvent.contextMenu(screen.getByTestId("artifact-1"));
+    const menu = screen.getByTestId("artifact-menu");
+    expect(within(menu).getByRole("menuitem", { name: "Delete" })).toBeInTheDocument();
+    expect(within(menu).queryByRole("menuitem", { name: "Install" })).toBeNull();
+    await user.click(within(menu).getByRole("menuitem", { name: "Preview" }));
+    expect(screen.queryByTestId("artifact-menu")).toBeNull();
+    expect((await screen.findByTestId("artifact-preview")).getAttribute("src")).toBe(
+      "/api/artifacts/1/raw?path=report.html"
+    );
+  });
 });

client/src/pages/__tests__/Users.test.tsx

@@ -5,14 +5,15 @@
  * with their own password typed (the confirm stays disabled until then), sees
  * a wrong password reported in the edit dialog, opens ONE Edit per row (no
  * separate role/password/workspace/disable buttons any more), and sees the
- * display name and email under a username.
+ * display name and email under a username; right-clicking a row opens that
+ * user's home in Files (an admin) — an analyst's menu only copies.
  * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
  */
 
 import { beforeEach, describe, expect, it, vi } from "vitest";
-import { fireEvent, render, screen, waitFor } from "@testing-library/react";
+import { fireEvent, render, screen, waitFor, within } from "@testing-library/react";
 import userEvent from "@testing-library/user-event";
-import { MemoryRouter, Route, Routes } from "react-router-dom";
+import { MemoryRouter, Route, Routes, useLocation } from "react-router-dom";
 import type { AuthState, ServerUserUsage } from "../../lib/api";
 
 let authState: AuthState = { mode: "local" };
@@ -60,12 +61,17 @@ vi.mock("../../lib/api", async (importOriginal) => {
 
 import { Users } from "../Users";
 
+function FilesProbe() {
+  return <div data-testid="files">{useLocation().search}</div>;
+}
+
 function renderPage() {
   return render(
     <MemoryRouter initialEntries={["/users"]}>
       <Routes>
         <Route path="/users" element={<Users />} />
         <Route path="/" element={<div data-testid="home" />} />
+        <Route path="/files" element={<FilesProbe />} />
       </Routes>
     </MemoryRouter>
   );
@@ -192,4 +198,23 @@ describe("Users page", () => {
     expect(screen.getByText("@mia")).toBeTruthy();
     expect(screen.getByText("mia@x.vn")).toBeTruthy();
   });
+
+  it("opens a row's menu on right-click: Open home for an admin, copy only for an analyst", async () => {
+    authState = { mode: "server", user: { id: 1, username: "boss", role: "admin" } };
+    renderPage();
+    fireEvent.contextMenu((await screen.findByText("mia")).closest("tr")!);
+    const menu = screen.getByTestId("users-row-menu");
+    expect(within(menu).getByRole("menuitem", { name: "Copy username" })).toBeTruthy();
+    fireEvent.click(within(menu).getByRole("menuitem", { name: "Open home in Files" }));
+    expect((await screen.findByTestId("files")).textContent).toBe("?home=mia");
+  });
+
+  it("gives an analyst's row menu no admin actions", async () => {
+    authState = { mode: "server", user: { id: 3, username: "ana", role: "analyst" } };
+    renderPage();
+    fireEvent.contextMenu((await screen.findByText("mia")).closest("tr")!);
+    const menu = screen.getByTestId("users-row-menu");
+    expect(within(menu).queryByRole("menuitem", { name: "Open home in Files" })).toBeNull();
+    expect(within(menu).queryByRole("menuitem", { name: "Edit" })).toBeNull();
+  });
 });