Shell: Give the TTY to the foreground process

This fixes the bug with the shell not waiting for any foreground process
that attempts to read from the terminal in the Lagom build.

Shell/Shell.cpp

@@ -522,6 +522,12 @@ RefPtr<Job> Shell::run_command(const AST::Command& command)
     if (child == 0) {
         setpgid(0, 0);
         tcsetattr(0, TCSANOW, &default_termios);
+        if (command.should_wait) {
+            auto pid = getpid();
+            auto pgid = getpgid(pid);
+            tcsetpgrp(STDOUT_FILENO, pgid);
+            tcsetpgrp(STDIN_FILENO, pgid);
+        }
         for (auto& rewiring : rewirings) {
 #ifdef SH_DEBUG
             dbgprintf("in %s<%d>, dup2(%d, %d)\n", argv[0], getpid(), rewiring.dest_fd, rewiring.source_fd);
@@ -618,7 +624,7 @@ Vector<RefPtr<Job>> Shell::run_commands(Vector<AST::Command>& commands)
                 jobs_to_wait_for.append(job);
             } else if (command.should_notify_if_in_background) {
                 job->set_running_in_background(true);
-                restore_stdin();
+                restore_ios();
             }
         }
     }
@@ -641,9 +647,11 @@ bool Shell::run_file(const String& filename, bool explicitly_invoked)
     run_command(data);
     return true;
 }
-void Shell::restore_stdin()
+void Shell::restore_ios()
 {
     tcsetattr(0, TCSANOW, &termios);
+    tcsetpgrp(STDOUT_FILENO, m_pid);
+    tcsetpgrp(STDIN_FILENO, m_pid);
 }
 
 void Shell::block_on_job(RefPtr<Job> job)
@@ -660,13 +668,13 @@ void Shell::block_on_job(RefPtr<Job> job)
         loop.quit(0);
     };
     if (job->exited()) {
-        restore_stdin();
+        restore_ios();
         return;
     }
 
     loop.exec();
 
-    restore_stdin();
+    restore_ios();
 }
 
 String Shell::get_history_path()
@@ -1030,7 +1038,7 @@ Vector<Line::CompletionSuggestion> Shell::complete_option(const String& program_
 
 bool Shell::read_single_line()
 {
-    restore_stdin();
+    restore_ios();
     auto line_result = editor->get_line(prompt());
 
     if (line_result.is_error()) {