feat: initialize project skeleton with Go backend, database, and config

- Go module with standard library + gorilla/sessions + mysql driver
- Config: env-based configuration with .env file support
- Database: MySQL connection with auto-migration for 6 tables
- Seed data: 12 system tags with options, 8 system snippets
- Auth: session cookie middleware
- Handlers: auth, tags, snippets, builder, claude, dashboard, suggestions, settings
- LLM: OpenAI-compatible client with 30s timeout
- Docker: Dockerfile + docker-compose.yml
- .env.example with all configuration options

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

internal/handlers/suggestions.go

@@ -0,0 +1,59 @@
+package handlers
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"prompt-generator/internal/llm"
+	"prompt-generator/internal/models"
+)
+
+func GetSuggestions(w http.ResponseWriter, r *http.Request) {
+	var req struct {
+		CurrentPrompt string `json:"current_prompt"`
+		ClaudeMD      string `json:"claude_md"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		fail(w, 400, "请求格式错误")
+		return
+	}
+
+	if req.CurrentPrompt == "" {
+		fail(w, 400, "当前 Prompt 不能为空")
+		return
+	}
+
+	client := llm.NewClient(cfg.LLMAPIBaseURL, cfg.LLMAPIKey, cfg.LLMModelName)
+	suggestions, err := client.GetSuggestions(req.CurrentPrompt, req.ClaudeMD)
+	if err != nil {
+		fail(w, 500, "获取建议失败: "+err.Error())
+		return
+	}
+
+	success(w, suggestions)
+}
+
+// parseSuggestions 尝试从 LLM 响应中解析建议列表
+func parseSuggestions(data string) []models.Suggestion {
+	// Try to find JSON array in the response
+	start := -1
+	end := -1
+	for i := 0; i < len(data); i++ {
+		if data[i] == '[' && start == -1 {
+			start = i
+		}
+		if data[i] == ']' {
+			end = i + 1
+		}
+	}
+
+	if start == -1 || end == -1 {
+		return nil
+	}
+
+	var suggestions []models.Suggestion
+	if err := json.Unmarshal([]byte(data[start:end]), &suggestions); err != nil {
+		return nil
+	}
+	return suggestions
+}