feat: v2.7.6 — edit users in one form, Settings → Account, display names, copy over plain HTTP

- Users page: one Edit user form (display name, email, role, active, a new or
  generated password, workspaces given or taken back, sign out everywhere),
  validated as a whole before anything is written (PATCH /api/users/:id,
  GET /api/users/:id); users.display_name/email added migration-safe.
- Settings → Account for every signed-in user: profile, own password (the
  current one required, this login kept), sign out other devices
  (/api/me/account, /api/me/password, /api/me/sign-out-others; login cookie
  only, never a pane token).
- Display names wherever a person is named (sidebar, workspace owner groups,
  Users page and audit log); owner_display_name / reader_display additive.
- Users page: admins add and remove Claude/Codex pool accounts.
- Folder browser: an admin with their own Linux account opens in their home;
  the "Server folder" tick opens the host's (never remembered).
- AI Proxy: "Config 9router" beside Add profile when 9router is installed,
  opened on the dashboard's own host (GET /api/ai-proxies/9router).
- Terminal: a tmux selection reaches the clipboard over plain HTTP too
  (writeClipboard's textarea fallback, focus handed back).
- Chat: a file the session touched outside the workspace previews
  (GET /api/sessions/:id/file).
- install-system: `!requiretty` only when visudo accepts it (sudo-rs on
  Ubuntu 25.10+ rejects the setting).
- openapi.yaml regenerated; docs (API, SERVER-MODE, LANES) updated.

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

scripts/server/install-system.sh

@@ -129,9 +129,15 @@ chmod 0755 /opt/agenthub/libexec/member-hook
 
 # ── sudoers: run-as members only (a fixed command list), and three root commands ──
 TMP_SUDOERS=$(mktemp)
+# `!requiretty` matters only where a distro turns requiretty ON (older RHEL);
+# sudo-rs (Ubuntu 25.10+) has no such setting and rejects the line, so it is
+# written only when this machine's visudo accepts it.
+NOTTY=""
+printf 'Defaults:%s !requiretty\n' "$HOST" >"$TMP_SUDOERS"
+visudo -cf "$TMP_SUDOERS" >/dev/null 2>&1 && NOTTY="Defaults:$HOST !requiretty"
 {
   echo "# AgentHub server mode (install-system). Members are never in sudoers."
-  echo "Defaults:$HOST !requiretty"
+  [ -z "$NOTTY" ] || echo "$NOTTY"
   echo "$HOST ALL=(%agenthub-members) NOPASSWD:SETENV: $TMUX_BIN, $GIT_BIN${GH_BIN:+, $GH_BIN}, /opt/agenthub/libexec/write-as, /opt/agenthub/tools/bin/claude"
   echo "$HOST ALL=(root) NOPASSWD: /opt/agenthub/sbin/agenthub-provision"
   for a in start stop restart enable disable; do