refactor: restructure tool target configs into tool package system

- Move tool configs from config/pkg/target/ to config/pkg/tool/
- Add ToolVersionRegistry for tracking installed tool versions
- Delete old Target/pkgconfig.php, move to tool config
- Rename: 7za-win, go-win, go-xcaddy, jom, nasm, protoc, strawberry-perl, upx, vswhere, zig, pkg-config

config/pkg/tool/vswhere.yml

@@ -0,0 +1,9 @@
+vswhere:
+  type: tool
+  artifact:
+    binary:
+      windows-x86_64: { type: url, url: 'https://github.com/microsoft/vswhere/releases/download/3.1.7/vswhere.exe', extract: '{pkg_root_path}/bin/vswhere.exe' }
+  tool:
+    provides:
+      - vswhere.exe
+    binary-subdir: bin