优化: 溢出修复与视觉token收敛+三处小清理

- diff长行折行可读/任务描述与产出宽表格横滚/确认弹窗长路径折行
- 滚动条色抽token浅色主题可见/阶段徽章与优先级色对齐语义token
- git状态色与错误色替换散落硬编码
- alert残留换toast走i18n/分离窗口缺参数补错误态/dev路由生产守卫

src/i18n/en/tasks.ts

@@ -127,6 +127,7 @@ export default {
       createFailed: 'Failed to create task',
       deleteFailed: 'Failed to delete task',
       updateFailed: 'Failed to update task',
+      selectProject: 'Please select a project',
     },
   },
 }

src/i18n/zh-CN/tasks.ts

@@ -127,6 +127,7 @@ export default {
       createFailed: '创建任务失败',
       deleteFailed: '删除任务失败',
       updateFailed: '更新任务失败',
+      selectProject: '请选择项目',
     },
   },
 }