feat: 新增关键词类型及优化查询逻辑

支持关键词类型区分，优化文件向量查询SQL及DAO更新逻辑，移除冗余配置和注释代码。

consts/keyword/type.go

@@ -0,0 +1,26 @@
+package keyword
+
+import "github.com/gogf/gf/v2/util/gconv"
+
+var (
+	KeywordTypeDefined = newKeywordType(gconv.PtrInt8(1), "自定义")
+	KeywordTypeInitial = newKeywordType(gconv.PtrInt8(2), "初始化")
+)
+
+type KeywordType *int8
+
+type keywordType struct {
+	code KeywordType
+	desc string
+}
+
+func (s keywordType) Code() KeywordType {
+	return s.code
+}
+func (s keywordType) Desc() string {
+	return s.desc
+}
+
+func newKeywordType(code KeywordType, desc string) keywordType {
+	return keywordType{code: code, desc: desc}
+}