feat: add users and sessions discovery

- also add clangd multi-file intellisense

src/main.c

@@ -1,3 +1,23 @@
+#include <pwd.h>
+#include <stdio.h>
+#include <sys/types.h>
+
+#include <sessions.h>
+#include <users.h>
+
 int main() {
-    return 2;
+  struct users_list *users = get_human_users();
+  struct sessions_list *sessions = get_avaliable_sessions();
+
+  printf("users(%hu) sessions(%hu)\n", users->length, sessions->length);
+
+  for (uint i = 0; i < users->length; i++)
+    printf("u[%d]: %s %s\n", i, users->users[i].username,
+           users->users[i].display_name);
+
+  for (uint i = 0; i < sessions->length; i++)
+    printf("s[%d]: %s %s\n", i, sessions->sessions[i].name,
+           sessions->sessions[i].path);
+
+  return 0;
 }