feat: 新增语音转文字（ASR）功能

- 后端：新增 /api/audio/transcribe 接口，调用 Ollama whisper 进行语音识别
- 前端：新增 AudioTranscribePage.vue 页面，支持 MP3/WAV/M4A/OGG/FLAC 等格式
- 注册路由、工具卡片、智能助手欢迎语更新

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

eai_agentplatform/backend-go/deploy/eaisalestrain.service

@@ -0,0 +1,33 @@
+[Unit]
+Description=eai_agentplatform 博昇内部培训平台后端
+After=network.target
+Wants=network.target
+
+[Service]
+Type=simple
+User=eai_agentplatform
+Group=eai_agentplatform
+WorkingDirectory=/opt/eai_agentplatform
+EnvironmentFile=-/opt/eai_agentplatform/.env
+ExecStart=/opt/eai_agentplatform/eai_agentplatform-server
+Restart=always
+RestartSec=3
+
+# 交付专用设备：最小权限 + 只读加固
+NoNewPrivileges=true
+ProtectSystem=strict
+ProtectHome=true
+ReadWritePaths=/opt/eai_agentplatform/data
+PrivateTmp=true
+PrivateDevices=true
+ProtectKernelTunables=true
+ProtectKernelModules=true
+ProtectControlGroups=true
+RestrictSUIDSGID=true
+
+# 端口占用到 8080 后自动释放，方便运维
+KillMode=mixed
+TimeoutStopSec=30
+
+[Install]
+WantedBy=multi-user.target