feat: add .gitignore to exclude common files, environments, and project-specific directories

.agent/rules/language.md

@@ -0,0 +1,5 @@
+---
+trigger: always_on
+---
+
+用中文回答

.gitignore

@@ -0,0 +1,28 @@
+# Python
+__pycache__/
+*.py[cod]
+*$py.class
+
+# Environments
+.env
+.venv/
+venv/
+ENV/
+env/
+
+# IDEs
+.vscode/
+.idea/
+
+# Database
+*.db
+*.sqlite3
+stock_analysis.db
+
+# OS
+.DS_Store
+
+# Project specific
+data/
+reports/
+logs/