Update TODO.md

TODO.md

@@ -1,6 +1,10 @@
 # TODO
 
-- Add incremental builds
 - Add header dependency tracking for incremental builds (GCC/Clang: -MMD, MSVC: /showIncludes)
 - Add external package managers (Conan, vcpkg)
-- Support building static libraries (ar .a)
+- Object library
+- Multi-target
+- ASM support
+- Linker script + direct linker control
+- Custom targets/steps
+- Tool overrides and env vars