Fix frontend UX: debounce saves, Zustand selectors, init race, dialog

- Debounce project config saves: use local state + save-on-blur instead
  of firing IPC requests on every keystroke in text inputs
- Add Zustand selectors to all store consumers to prevent full-store
  re-renders on any state change
- Fix initialization race: chain checkImage after checkDocker resolves
- Fix DockerSettings setTimeout race: await checkImage after save
- Add console.error logging to all 11 empty catch blocks in ProjectCard
- Add keyboard support to AddProjectDialog: Escape to close,
  click-outside-to-close, form submit on Enter, auto-focus

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/src/hooks/useProjects.ts

@@ -1,4 +1,5 @@
 import { useCallback } from "react";
+import { useShallow } from "zustand/react/shallow";
 import { useAppState } from "../store/appState";
 import * as commands from "../lib/tauri-commands";
 
@@ -10,7 +11,16 @@ export function useProjects() {
     setSelectedProject,
     updateProjectInList,
     removeProjectFromList,
-  } = useAppState();
+  } = useAppState(
+    useShallow(s => ({
+      projects: s.projects,
+      selectedProjectId: s.selectedProjectId,
+      setProjects: s.setProjects,
+      setSelectedProject: s.setSelectedProject,
+      updateProjectInList: s.updateProjectInList,
+      removeProjectFromList: s.removeProjectFromList,
+    }))
+  );
 
   const selectedProject = projects.find((p) => p.id === selectedProjectId) ?? null;