feat: structure view in dashboard and settings persistence

- Add GET /api/claude/sessions/{session_id}/builder API for structure view
- Load builder session tags and snippets by Claude session ID
- Implement structure view in dashboard: shows tag selections and snippet details
- Add LoadSettings to persist LLM config changes across restarts
- Settings are now loaded from database on startup

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

internal/db/db.go

@@ -109,6 +109,36 @@ func AutoMigrate() error {
 	return nil
 }
 
+// LoadSettings loads persisted settings from the database into config
+func LoadSettings(cfg *config.Config) {
+	// Create settings table if not exists
+	DB.Exec(`CREATE TABLE IF NOT EXISTS settings (
+		key_name varchar(64) NOT NULL PRIMARY KEY,
+		value text NOT NULL
+	) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4`)
+
+	rows, err := DB.Query("SELECT key_name, value FROM settings")
+	if err != nil {
+		return
+	}
+	defer rows.Close()
+
+	for rows.Next() {
+		var key, value string
+		if err := rows.Scan(&key, &value); err != nil {
+			continue
+		}
+		switch key {
+		case "llm_api_base_url":
+			cfg.LLMAPIBaseURL = value
+		case "llm_api_key":
+			cfg.LLMAPIKey = value
+		case "llm_model_name":
+			cfg.LLMModelName = value
+		}
+	}
+}
+
 // EnsurePromptsTable creates the prompts table if it doesn't exist (for dev environments)
 func EnsurePromptsTable() {
 	_, err := DB.Exec(`CREATE TABLE IF NOT EXISTS prompts (

internal/handlers/claude.go

@@ -4,6 +4,7 @@ import (
 	"net/http"
 
 	"prompt-generator/internal/db"
+	"prompt-generator/internal/models"
 )
 
 func GetClaudeSessions(w http.ResponseWriter, r *http.Request) {
@@ -47,6 +48,81 @@ func GetClaudeSessions(w http.ResponseWriter, r *http.Request) {
 	success(w, sessions)
 }
 
+// GetBuilderSessionByClaudeSession looks up a builder session by claude_session_id
+func GetBuilderSessionByClaudeSession(w http.ResponseWriter, r *http.Request) {
+	sessionID := r.PathValue("session_id")
+	if sessionID == "" {
+		fail(w, 400, "session_id 必填")
+		return
+	}
+
+	var s models.BuilderSession
+	err := db.DB.QueryRow("SELECT id, title, project_name, final_prompt, claude_session_id, created_at, updated_at FROM builder_sessions WHERE claude_session_id=?", sessionID).
+		Scan(&s.ID, &s.Title, &s.ProjectName, &s.FinalPrompt, &s.ClaudeSessionID, &s.CreatedAt, &s.UpdatedAt)
+	if err != nil {
+		// Not found is not an error
+		success(w, nil)
+		return
+	}
+
+	// Load tags with details
+	tags := []map[string]interface{}{}
+	tagRows, err := db.DB.Query(`
+		SELECT bst.tag_id, bst.tag_option_id, t.name, to2.label, to2.constraint_text
+		FROM builder_session_tags bst
+		JOIN tags t ON t.id = bst.tag_id
+		JOIN tag_options to2 ON to2.id = bst.tag_option_id
+		WHERE bst.builder_session_id=?`, s.ID)
+	if err == nil {
+		for tagRows.Next() {
+			var tagID, optionID int64
+			var tagName, optionLabel, constraintText string
+			if err := tagRows.Scan(&tagID, &optionID, &tagName, &optionLabel, &constraintText); err == nil {
+				tags = append(tags, map[string]interface{}{
+					"tag_id":          tagID,
+					"tag_option_id":   optionID,
+					"tag_name":        tagName,
+					"option_label":    optionLabel,
+					"constraint_text": constraintText,
+				})
+			}
+		}
+		tagRows.Close()
+	}
+
+	// Load snippets with details
+	snippets := []map[string]interface{}{}
+	snippetRows, err := db.DB.Query(`
+		SELECT bss.snippet_id, s.name, s.content, s.category, bss.sort_order
+		FROM builder_session_snippets bss
+		JOIN snippets s ON s.id = bss.snippet_id
+		WHERE bss.builder_session_id=?
+		ORDER BY bss.sort_order`, s.ID)
+	if err == nil {
+		for snippetRows.Next() {
+			var snippetID int64
+			var name, content, category string
+			var sortOrder int
+			if err := snippetRows.Scan(&snippetID, &name, &content, &category, &sortOrder); err == nil {
+				snippets = append(snippets, map[string]interface{}{
+					"snippet_id": snippetID,
+					"name":       name,
+					"content":    content,
+					"category":   category,
+					"sort_order": sortOrder,
+				})
+			}
+		}
+		snippetRows.Close()
+	}
+
+	success(w, map[string]interface{}{
+		"session":  s,
+		"tags":     tags,
+		"snippets": snippets,
+	})
+}
+
 func GetClaudePrompts(w http.ResponseWriter, r *http.Request) {
 	sessionID := r.PathValue("session_id")
 	if sessionID == "" {