feat: implement sessions, lobby, roles, and rematch lifecycle

include/session_manager.h

@@ -1,7 +1,40 @@
 #pragma once
 
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "app_interfaces.h"
 #include "app_config.h"
 #include "game_types.h"
 
-typedef struct { role_t role; bool occupied; uint8_t token[kSessionTokenBytes]; char name[kDisplayNameBytes + 1]; } session_t;
+typedef uint8_t session_result_t;
+enum {
+  SESSION_RESULT_OK,
+  SESSION_RESULT_INVALID_NAME,
+  SESSION_RESULT_INVALID_ROLE,
+  SESSION_RESULT_NO_PLAYER_SLOT,
+  SESSION_RESULT_NO_SPECTATOR_SLOT,
+  SESSION_RESULT_UNAUTHORIZED,
+  SESSION_RESULT_WRONG_PHASE,
+};
+
+typedef struct {
+  role_t role;
+  bool occupied;
+  bool connected;
+  uint8_t token[kSessionTokenBytes];
+  char name[kDisplayNameBytes + 1];
+} session_t;
 typedef struct { session_t entries[kSessionCapacity]; } session_manager_t;
+
+void session_manager_init(session_manager_t *manager);
+session_result_t session_manager_join(session_manager_t *manager, role_t requested_role, const char *name,
+                                      random_source_t random, uint8_t *session_index);
+session_result_t session_manager_resume(session_manager_t *manager, const uint8_t token[kSessionTokenBytes],
+                                        uint8_t *session_index);
+bool session_manager_disconnect(session_manager_t *manager, uint8_t session_index);
+session_result_t session_manager_leave(session_manager_t *manager, uint8_t session_index, phase_t phase);
+bool session_manager_player_present(const session_manager_t *manager, uint8_t player_index);
+
+_Static_assert(sizeof(session_t) <= 104, "session grew beyond fixed budget");
+_Static_assert(sizeof(session_manager_t) <= 1040, "session table grew beyond fixed budget");