chore: organize code

add -Wextra by default
pipefd to communicate better with parent and forked process
rustify some stuff
add the desktop parser to the file read

include/auth.h

@@ -6,7 +6,8 @@
 #include "config.h"
 #include "sessions.h"
 
-bool launch(char* user, char* passwd, struct session session, void (*cb)(void),
-            struct config* config);
+bool launch(char* NNULLABLE user, char* NNULLABLE passwd,
+            struct session session, void (*NULLABLE cb)(void),
+            struct config* NNULLABLE config);
 
 #endif