develop/ktcc: Post-SVN tidy

- Move source code from `trunk` into program root directory.
- Update build files and include paths.
- These changes also update the CI build files in `.gitea/workflows/`.
- Note: Line endings standardised from `CRLF` > `LF`, so best to view diffs with whitespace changes hidden.

programs/develop/ktcc/lib/libshell/shell_getc.c

@@ -0,0 +1,9 @@
+#include "shell_api.h"
+
+char shell_getc()
+{
+    __shell_init();
+    *__shell_shm = SHELL_GETC;
+    __SHELL_WAIT();
+    return *(__shell_shm+1);
+}