refactor: restructure project layout

- Move main process to electron/main/
- Move preload to electron/preload/
- Add shared types in electron/shared/
- Split redis-service into modular redis/ directory
- Flatten renderer to src/ (remove src/renderer/ nesting)
- Update electron.vite.config.ts paths
- Update tsconfig paths
- Output to electron-dist/

src/components/StatusBar.vue

@@ -0,0 +1,100 @@
+<script setup lang="ts">
+// src/renderer/src/components/StatusBar.vue
+import { computed } from 'vue'
+import { useConnectionStore } from '@renderer/stores/connection'
+import DbSelector from './DbSelector.vue'
+
+const connStore = useConnectionStore()
+
+const statusText = computed(() => {
+  if (connStore.connecting) return 'Connecting...'
+  if (connStore.error) return `Error: ${connStore.error}`
+  if (connStore.activeConnection) {
+    return `${connStore.activeConnection.host}:${connStore.activeConnection.port}`
+  }
+  return 'No connection'
+})
+
+const statusClass = computed(() => {
+  if (connStore.connecting) return 'status-connecting'
+  if (connStore.error) return 'status-error'
+  if (connStore.isConnected && connStore.healthOk) return 'status-connected'
+  if (connStore.isConnected && !connStore.healthOk) return 'status-unstable'
+  return 'status-disconnected'
+})
+</script>
+
+<template>
+  <footer class="statusbar">
+    <span class="statusbar-left">
+      <span class="status-dot" :class="statusClass" />
+      {{ statusText }}
+    </span>
+    <span class="statusbar-center">
+      <DbSelector v-if="connStore.isConnected" />
+    </span>
+    <span class="statusbar-right">JRedisDesktop v2.0</span>
+  </footer>
+</template>
+
+<style scoped>
+.statusbar {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  height: 26px;
+  padding: 0 14px;
+  background: var(--bg-secondary);
+  border-top: 1px solid var(--border-color);
+  font-size: 11px;
+  color: var(--text-muted);
+  flex-shrink: 0;
+  user-select: none;
+}
+
+.statusbar-left {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+}
+
+.statusbar-center {
+  flex: 1;
+  display: flex;
+  justify-content: center;
+}
+
+.status-dot {
+  width: 7px;
+  height: 7px;
+  border-radius: 50%;
+  background: var(--text-muted);
+}
+
+.status-dot.status-connected {
+  background: var(--success);
+  box-shadow: 0 0 6px var(--success);
+}
+
+.status-dot.status-connecting {
+  background: var(--warning);
+  box-shadow: 0 0 6px var(--warning);
+  animation: pulse 1s infinite;
+}
+
+.status-dot.status-error {
+  background: var(--danger);
+  box-shadow: 0 0 6px var(--danger);
+}
+
+.status-dot.status-unstable {
+  background: var(--warning);
+  box-shadow: 0 0 6px var(--warning);
+  animation: pulse 2s infinite;
+}
+
+@keyframes pulse {
+  0%, 100% { opacity: 1; }
+  50% { opacity: 0.4; }
+}
+</style>