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/Users.tsx

@@ -13,14 +13,15 @@
  * tmux server beside the installed version, restartable by an admin
  * (`MemberTmuxCard`). Every change asks for the admin's OWN password again (the
  * server refuses without it); an analyst only reads. A row shows the display
- * name and email under the username when set.
+ * name and email under the username when set; right-clicking a row offers
+ * Edit, Open home (in /files), and copying the username or email.
  * Laid out like the other list pages: icon header, a row of totals
  * (`StatCard`), the accounts in a `card` table, the audit log in a card.
  * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
  */
 
 import { useCallback, useEffect, useState, type KeyboardEvent, type ReactNode } from "react";
-import { Navigate } from "react-router-dom";
+import { Navigate, useNavigate } from "react-router-dom";
 import { useTranslation } from "react-i18next";
 import {
   AlertCircle,
@@ -52,6 +53,8 @@ import { ROLE_BADGE, UserEditDialog } from "../components/users/UserEditDialog";
 import { AccountPoolCard } from "../components/users/AccountPoolCard";
 import { MemberTmuxCard } from "../components/users/MemberTmuxCard";
 import { TableRowSkeleton } from "../components/Skeleton";
+import { ContextMenu, MenuItem, MenuSeparator, useContextMenu } from "../components/ContextMenu";
+import { copyText } from "../lib/clipboard";
 
 type Role = AuthUser["role"];
 const ROLES: Role[] = ["admin", "analyst", "developer"];
@@ -67,6 +70,8 @@ export function Users() {
   const [error, setError] = useState<string | null>(null);
   const [adding, setAdding] = useState(false);
   const [editing, setEditing] = useState<ServerUserUsage | null>(null);
+  const rowMenu = useContextMenu<ServerUserUsage>();
+  const navigate = useNavigate();
   const [storage, setStorage] = useState<Record<string, UserStorage> | null>(null);
   const [measuring, setMeasuring] = useState(false);
 
@@ -231,6 +236,7 @@ export function Users() {
               return (
                 <tr
                   key={u.id}
+                  onContextMenu={(e) => rowMenu.open(e, u)}
                   className={`hover:bg-surface-4/40 transition-colors ${u.disabled ? "opacity-60" : ""}`}
                 >
                   <td className="px-5 py-3">
@@ -298,6 +304,47 @@ export function Users() {
         </table>
       </div>
 
+      {rowMenu.menu &&
+        (() => {
+          const u = rowMenu.menu.item;
+          const pick = (fn: () => void) => () => {
+            rowMenu.close();
+            fn();
+          };
+          return (
+            <ContextMenu
+              x={rowMenu.menu.x}
+              y={rowMenu.menu.y}
+              onClose={rowMenu.close}
+              testId="users-row-menu"
+            >
+              {isAdmin && (
+                <MenuItem onSelect={pick(() => setEditing(u))}>{t("edit.button")}</MenuItem>
+              )}
+              {isAdmin && !u.disabled && (
+                <MenuItem
+                  onSelect={pick(() =>
+                    navigate(
+                      `/files?home=${encodeURIComponent(u.id === me.id ? "me" : u.username)}`
+                    )
+                  )}
+                >
+                  {t("rowMenu.openHome")}
+                </MenuItem>
+              )}
+              {isAdmin && <MenuSeparator />}
+              <MenuItem onSelect={pick(() => void copyText(u.username))}>
+                {t("rowMenu.copyUsername")}
+              </MenuItem>
+              {u.email && (
+                <MenuItem onSelect={pick(() => void copyText(u.email!))}>
+                  {t("rowMenu.copyEmail")}
+                </MenuItem>
+              )}
+            </ContextMenu>
+          );
+        })()}
+
       <AccountPoolCard isAdmin={isAdmin} />
       <MemberTmuxCard isAdmin={isAdmin} />