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/internal/api/note.go

@@ -0,0 +1,137 @@
+package api
+
+import (
+	"strconv"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+
+	"eai_agentplatform/backend/internal/middleware"
+	"eai_agentplatform/backend/internal/model"
+	"eai_agentplatform/backend/internal/store"
+	"eai_agentplatform/backend/internal/web"
+)
+
+var validNoteItemTypes = map[string]bool{"company": true, "product": true, "course": true}
+
+// ListNotes GET /api/notes?item_type=&item_id= —— 我的学习笔记
+func ListNotes(c *gin.Context) {
+	u := middleware.CurrentUser(c)
+	if u == nil {
+		web.Fail(c, web.NewAuthError("未登录"))
+		return
+	}
+	q := store.DB.Where("user_id = ?", u.ID)
+	if t := c.Query("item_type"); t != "" {
+		q = q.Where("item_type = ?", t)
+	}
+	if s := c.Query("item_id"); s != "" {
+		if n, err := strconv.ParseUint(s, 10, 64); err == nil {
+			q = q.Where("item_id = ?", n)
+		}
+	}
+	var items []model.StudyNote
+	if err := q.Order("updated_at DESC").Find(&items).Error; err != nil {
+		web.Fail(c, web.NewBadRequest("查询笔记失败"))
+		return
+	}
+	web.OK(c, items)
+}
+
+// CreateNote POST /api/notes —— 新增学习笔记
+func CreateNote(c *gin.Context) {
+	u := middleware.CurrentUser(c)
+	if u == nil {
+		web.Fail(c, web.NewAuthError("未登录"))
+		return
+	}
+	var req struct {
+		ItemType string `json:"item_type"`
+		ItemID   uint   `json:"item_id"`
+		Content  string `json:"content"`
+	}
+	if err := c.ShouldBindJSON(&req); err != nil {
+		web.Fail(c, web.NewBadRequest("请求参数错误"))
+		return
+	}
+	if !validNoteItemTypes[req.ItemType] {
+		web.Fail(c, web.NewBadRequest("item_type 必须为 company/product/course"))
+		return
+	}
+	if strings.TrimSpace(req.Content) == "" {
+		web.Fail(c, web.NewBadRequest("笔记内容不能为空"))
+		return
+	}
+	n := model.StudyNote{UserID: u.ID, ItemType: req.ItemType, ItemID: req.ItemID, Content: strings.TrimSpace(req.Content)}
+	if err := store.DB.Create(&n).Error; err != nil {
+		web.Fail(c, web.NewBadRequest("保存笔记失败"))
+		return
+	}
+	web.OK(c, n)
+}
+
+// UpdateNote PUT /api/notes/{id} —— 编辑学习笔记
+func UpdateNote(c *gin.Context) {
+	u := middleware.CurrentUser(c)
+	if u == nil {
+		web.Fail(c, web.NewAuthError("未登录"))
+		return
+	}
+	id, ok := parseID(c, "id")
+	if !ok {
+		return
+	}
+	var n model.StudyNote
+	if err := store.DB.First(&n, id).Error; err != nil {
+		web.Fail(c, web.NewNotFoundError("笔记不存在"))
+		return
+	}
+	if n.UserID != u.ID {
+		web.Fail(c, web.NewForbiddenError("无权操作他人笔记"))
+		return
+	}
+	var req struct {
+		Content string `json:"content"`
+	}
+	if err := c.ShouldBindJSON(&req); err != nil {
+		web.Fail(c, web.NewBadRequest("请求参数错误"))
+		return
+	}
+	if strings.TrimSpace(req.Content) == "" {
+		web.Fail(c, web.NewBadRequest("笔记内容不能为空"))
+		return
+	}
+	n.Content = strings.TrimSpace(req.Content)
+	if err := store.DB.Save(&n).Error; err != nil {
+		web.Fail(c, web.NewBadRequest("更新笔记失败"))
+		return
+	}
+	web.OK(c, n)
+}
+
+// DeleteNote DELETE /api/notes/{id} —— 删除学习笔记
+func DeleteNote(c *gin.Context) {
+	u := middleware.CurrentUser(c)
+	if u == nil {
+		web.Fail(c, web.NewAuthError("未登录"))
+		return
+	}
+	id, ok := parseID(c, "id")
+	if !ok {
+		return
+	}
+	var n model.StudyNote
+	if err := store.DB.First(&n, id).Error; err != nil {
+		web.Fail(c, web.NewNotFoundError("笔记不存在"))
+		return
+	}
+	if n.UserID != u.ID {
+		web.Fail(c, web.NewForbiddenError("无权操作他人笔记"))
+		return
+	}
+	if err := store.DB.Delete(&n).Error; err != nil {
+		web.Fail(c, web.NewBadRequest("删除笔记失败"))
+		return
+	}
+	web.OK(c, gin.H{"id": id})
+}