patch 8.2.0783: libvterm code lags behind the upstream version

Problem:    Libvterm code lags behind the upstream version.
Solution:   Include revisions 728 - 729.

src/libvterm/t/25state_input.test

@@ -111,6 +111,18 @@ PUSH "\e[20h"
 INKEY 0 Enter
   output "\x0d\x0a"
 
+!Unmodified F1 is SS3 P
+INKEY 0 F1
+  output "\eOP"
+
+!Modified F1 is CSI P
+INKEY S F1
+  output "\e[1;2P"
+INKEY A F1
+  output "\e[1;3P"
+INKEY C F1
+  output "\e[1;5P"
+
 !Keypad in DECKPNM
 INKEY 0 KP0
   output "0"

src/libvterm/t/26state_query.test

@@ -59,4 +59,4 @@ PUSH "\e F"
 
 !Truncation on attempted buffer overflow
 PUSH "\e[6n" x 30
-  output "\e[10;10R" x 24
+  output "\e[10;10R" x 25

src/libvterm/t/harness.c

@@ -47,6 +47,7 @@ static VTermKey strp_key(char *str)
     { "Tab",   VTERM_KEY_TAB },
     { "Enter", VTERM_KEY_ENTER },
     { "KP0",   VTERM_KEY_KP_0 },
+    { "F1",    VTERM_KEY_FUNCTION(1) },
     { NULL,    VTERM_KEY_NONE },
   };
   int i;