Merge upstream/main into the Spanning Tree branch

cmd_parser.c conflicted twice: main rewrote the pvid command around the
new port-separator and atoi helpers, next to the line where this branch
delegates "stp" to stp_parse(). Both belong, so the STP delegation keeps
main's pvid body.

The linker caught what the merge could not see: main changed atoi_byte()
to return the digit count and leave the value in atoi_results_u8, where
it used to return non-zero on failure and write through a pointer. Note
the sense is inverted, so the three calls in rtl837x_stp.c are adjusted
rather than just re-arranged.

httpd/page_impl.h

@@ -1,7 +1,9 @@
 #ifndef __PAGE_IMPL_H__
 #define __PAGE_IMPL_H__
 
-void send_counters(char port);
+#include <stdbool.h>
+
+bool send_counters(uint8_t phys_port);
 void send_status(void);
 void send_vlan(uint16_t vlan);
 void send_basic_info(void);