feat(iidx19): imagefs override strategy with local file redir

src/imports/avs.h

@@ -231,6 +231,7 @@ void property_node_datasize(struct property_node *node);
 bool std_getenv(const char *key, char *val, uint32_t nbytes);
 void std_setenv(const char *key, const char *val);
 
+void* avs_fs_open(const char* path, int mode, int flags);
 int avs_fs_addfs(void *filesys_struct);
 int avs_fs_mount(
     const char *mountpoint, const char *fsroot, const char *fstype, void *data);

src/imports/import_32_1304_avs.def

@@ -2,6 +2,7 @@ LIBRARY libavs-win32
 
 EXPORTS
     avs_boot @237 NONAME
+    avs_fs_open @178 NONAME
     avs_net_ctrl @15 NONAME
     avs_shutdown @333 NONAME
     avs_thread_create @183 NONAME
@@ -25,4 +26,4 @@ EXPORTS
     property_read_query_memsize @100 NONAME
     property_search @244 NONAME
     std_getenv @226 NONAME
-    std_setenv  @114 NONAME
+    std_setenv @114 NONAME