Refactor: Remove outdated security requirements and best practice templates

- Deleted security requirements specification file to streamline documentation.
- Removed best practice finding template to enhance clarity and focus on critical issues.
- Eliminated report template and security finding template to reduce redundancy and improve maintainability.
- Updated skill generator templates to enforce mandatory prerequisites for better compliance with design standards.
- Bumped package version from 6.3.18 to 6.3.23 for dependency updates.

.claude/skills/skill-generator/templates/sequential-phase.md

@@ -2,6 +2,15 @@
 
 顺序模式 Phase 文件的模板。
 
+## ⚠️ 重要提示
+
+> **Phase 0 是强制前置阶段**：在实现任何 Phase (1, 2, 3...) 之前，必须先完成 Phase 0 的规范研读。
+>
+> 生成 Sequential Phase 时，需要确保：
+> 1. SKILL.md 中已包含 Phase 0 规范研读步骤
+> 2. 每个 Phase 文件都引用相关的规范文档
+> 3. 执行流程明确标注 Phase 0 为禁止跳过的前置步骤
+
 ## 模板结构
 
 ```markdown