Expand CI environments in TODO.md

- Mark basic GitHub Actions and Ubuntu Latest as completed
- Add detailed breakdown of target test environments:
  - Various Linux distributions
  - macOS variants
  - Windows environments (WSL2, native, Git Bash)

TODO.md

@@ -39,8 +39,23 @@
 ## Development Infrastructure
 
 ### CI/CD Setup
-- [ ] Set up basic GitHub Actions workflow
+- [x] Set up basic GitHub Actions workflow ✅ 2025-01-12
 - [ ] Add automated testing across different environments
+  - [x] Ubuntu Latest (GitHub Actions) ✅ 2025-01-12
+  - [ ] Other Linux distributions
+    - [ ] Fedora Latest
+    - [ ] Debian Stable
+    - [ ] Arch Linux
+    - [ ] Alpine Linux (minimal environment test)
+  - [ ] macOS
+    - [ ] macOS Latest (GitHub Actions)
+    - [ ] macOS Intel
+    - [ ] macOS ARM (M1/M2)
+  - [ ] Windows
+    - [ ] Windows WSL2 (Ubuntu)
+    - [ ] Windows WSL2 (Debian)
+    - [ ] Native Windows with PowerShell
+    - [ ] Windows with Git Bash
 - [ ] Add automated release process
 - [ ] Add code quality checks