refactor(floorplan): 重构平面图组件与样式

- 移除未使用的编辑模式、热力图、搜索等功能
- 将样式代码抽离到独立样式文件
- 优化工具栏和缩放控制组件实现
- 添加导出图片功能
- 简化上下文状态管理
- 优化设备提示框和空状态显示

frontend/src/components/floorplan/canvas/CanvasConstants.js

@@ -1,35 +1,16 @@
-// 机柜卡片基础尺寸（会根据屏幕自适应调整）
 export const CELL_WIDTH = 220;
 export const CELL_HEIGHT = 480;
 export const CELL_GAP = 20;
 
-// 兼容旧引用
-export const CELL_SIZE = 220;
-export const ROW_LABEL_WIDTH = 50;
-export const COL_LABEL_HEIGHT = 30;
-
-// 机柜内部尺寸
 export const RACK_PADDING = 10;
 export const RACK_HEADER_HEIGHT = 36;
 export const RACK_STATUS_BAR_HEIGHT = 4;
 
-// U位显示尺寸（双边）
 export const U_HEIGHT = 10;
 export const U_LABEL_WIDTH_LEFT = 28;
 export const U_LABEL_WIDTH_RIGHT = 28;
 export const U_BODY_WIDTH = 154;
-export const U_BODY_PADDING = 6;
 
-// 设备显示尺寸
-export const DEVICE_INDICATOR_WIDTH = 3;
-export const DEVICE_STATUS_DOT_SIZE = 2.5;
-export const DEVICE_NAME_MAX_WIDTH = 130;
-
-// 小地图
-export const MINI_MAP_SIZE = 160;
-export const MINI_MAP_PADDING = 10;
-
-// 缩放参数
 export const ZOOM = {
   MIN: 0.3,
   MAX: 2,
@@ -38,23 +19,18 @@ export const ZOOM = {
   WHEEL_FACTOR: 0.001,
 };
 
-// 颜色定义
-export const COLORS = {
-  CANVAS_BG: '#f0f2f5',
-  RACK_BG: '#ffffff',
-  RACK_BORDER: '#d9d9d9',
-  RACK_SHADOW: 'rgba(0,0,0,0.08)',
-  RACK_HEADER_BG: '#fafafa',
-  EMPTY_U_BG: '#f5f5f5',
-  GRID_LINE: '#e8e8e8',
-};
-
 export const RACK_STATUS_COLORS = {
   active: '#1677ff',
   maintenance: '#faad14',
   inactive: '#bfbfbf',
 };
 
+export const RACK_STATUS_NAMES = {
+  active: '在用',
+  maintenance: '维护中',
+  inactive: '停用',
+};
+
 export const DEVICE_TYPE_COLORS = {
   server: '#1677ff',
   switch: '#52c41a',
@@ -64,6 +40,15 @@ export const DEVICE_TYPE_COLORS = {
   other: '#8c8c8c',
 };
 
+export const DEVICE_TYPE_NAMES = {
+  server: '服务器',
+  switch: '交换机',
+  router: '路由器',
+  firewall: '防火墙',
+  storage: '存储设备',
+  other: '其他',
+};
+
 export const DEVICE_STATUS_COLORS = {
   running: '#52c41a',
   maintenance: '#faad14',
@@ -72,13 +57,14 @@ export const DEVICE_STATUS_COLORS = {
   idle: '#d9d9d9',
 };
 
-export const HEAT_MAP = {
-  LOW: '#52c41a',
-  MEDIUM: '#faad14',
-  HIGH: '#ff4d4f',
+export const DEVICE_STATUS_NAMES = {
+  running: '运行中',
+  maintenance: '维护中',
+  offline: '离线',
+  fault: '故障',
+  idle: '空闲',
 };
 
-// 字体定义
 export const FONT = {
   RACK_NAME: 'bold 13px -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif',
   RACK_INFO: '10px -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif',