chore: 补充忽略 AI 工具本地目录与构建产物

新增 .flattened-pom.xml、node_modules、各类 AI 工具目录
（.claude/.codex/.workbuddy/... 共 30+）的忽略规则，避免
本地工具痕迹进入版本控制

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitignore

@@ -3,6 +3,49 @@
 /water-modules/*/target/
 /logs/
 /water-extend/*/target/
+/.flattened-pom.xml
+/**/.flattened-pom.xml
+
+# Node / local AI tooling
+/node_modules/
+/package-lock.json
+/package.json
+/skills-lock.json
+/.codegraph/
+/.agent/
+/.agents/
+/.amazonq/
+/.augment/
+/.bob/
+/.claude/
+/.cline/
+/.clinerules/
+/.codebuddy/
+/.codex/
+/.comet/
+/.continue/
+/.cospec/
+/.crush/
+/.cursor/
+/.factory/
+/.forge/
+/.gemini/
+/.github/
+/.iflow/
+/.junie/
+/.kilocode/
+/.kimi/
+/.kimi-code/
+/.kiro/
+/.lingma/
+/.opencode/
+/.pi/
+/.qoder/
+/.qwen/
+/.roo/
+/.trae/
+/.windsurf/
+/.workbuddy/
 
 # IDE
 .idea/