Complete device config API integration

[srgvg]

Context

Device config pages use only 2 of 11 functions from deviceConfig.ts (detectConfigDrift, getConfigHistory). The remaining 9 functions cover core device configuration management that needs to be wired up.

API Functions to Wire Up

• getDeviceConfig - Retrieve device configuration
• updateDeviceConfig - Update device configuration
• getCurrentDeviceConfig - Get current live config from device
• getNormalizedCurrentConfig - Get normalized config for comparison
• importDeviceConfig - Import configuration to device
• exportDeviceConfig - Export device configuration
• applyConfigTemplate - Apply a configuration template to device
• bulkApplyConfig - Apply config to multiple devices
• getConfigDiff - Get diff between two configurations

Affected Files

• ui/src/api/deviceConfig.ts - API module (11 functions defined, 2 used)
• ui/src/stores/deviceConfig.ts - Pinia store
• ui/src/pages/DeviceDetailPage.vue
• ui/src/pages/DeviceConfigPage.vue

Acceptance Criteria

• Device config read/update cycle works end-to-end
• Live config retrieval from device functional
• Config import/export operations work
• Template application to device works
• Bulk config apply operational
• Config diff view shows meaningful comparison
• Error handling and loading states for all operations