feat: refactor to proper Go structure and add folder/recursive support

- Refactor to cmd/internal structure following Go best practices
- Add support for processing directories (files in folder)
- Add -r/--recursive flag for recursive directory traversal
- Split code into logical packages: types, processor, languages
- Fix --version flag to work properly with kong
- Update build path in GitHub Actions workflow
- Version bump to 0.1.0 for new major features

.github/workflows/release.yml

@@ -57,7 +57,7 @@ jobs:
           CGO_ENABLED: 0
           CC: ${{ matrix.platform.arch == 'aarch64' && matrix.platform.os == 'linux' && 'aarch64-linux-gnu-gcc' || '' }}
         run: |
-          go build -ldflags="-w -s" -o shush .
+          go build -ldflags="-w -s" -o shush ./cmd/shush
 
       - name: Prepare binary
         shell: bash