v0.321.0: FileBrowser's stale password and its own banners; one backup section on the Data tab; install address of an installed app

R-1101: the change-it line is gone for FileBrowser; in the generated state the page asks FileBrowser whether
the stored password still logs in (only its own 401/403 counts) and, refused, says so and offers the
new-password press. The rendered FileBrowser config switches off its update notice and its Install-app
prompt. The Data tab's backup part is one section in plain words (no off-drive, no PBS); the export
password eye is a text button. R-1095: /apps/{slug}/install of an installed app 302s to its settings tab.

Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/internal/web/app_page.go

@@ -245,6 +245,12 @@ func (s *Server) appInstallPageHandler(w http.ResponseWriter, r *http.Request, s
 		http.Redirect(w, r, s.cfg.AppPageURL(slug), http.StatusFound)
 		return
 	}
+	// v0.321.0 (R-1095): an INSTALLED app's install address — typed, bookmarked, or an old link — goes to its
+	// settings tab, the redirectStackDeployGET shape. It used to render the install form read-only, with no button.
+	if st := s.stackBySlug(slug); st != nil && st.Deployed {
+		http.Redirect(w, r, s.cfg.AppPageURL(slug)+"/"+appTabSettings, http.StatusFound)
+		return
+	}
 	s.deployHandler(w, r, name)
 }