refine .gitignore for VSCode, Pi Pico, and CMake

.gitignore

@@ -4,9 +4,7 @@
 
 # Object files
 *.o
-*.ko
 *.obj
-*.elf
 
 # Linker output
 *.ilk
@@ -23,34 +21,12 @@
 *.la
 *.lo
 
-# Shared objects (inc. Windows DLLs)
-*.dll
-*.so
-*.so.*
-*.dylib
-
 # Executables
-*.exe
-*.out
-*.app
-*.i*86
-*.x86_64
-*.hex
-
-# Debug files
-*.dSYM/
-*.su
-*.idb
-*.pdb
+*.elf
 
-# Kernel Module Compile Results
-*.mod*
-*.cmd
-.tmp_versions/
-modules.order
-Module.symvers
-Mkfile.old
-dkms.conf
+# ---> CMake
+# Build Directory
+build/*
 
 # ---> VisualStudioCode
 .vscode/*