fix(market): raise resource input maxlength so high-speed servers can send full convoys

The send/trade-route resource fields were capped at maxlength="5", limiting
input to 99,999 per resource. On high-speed servers a single convoy carries far
more (e.g. Teutons: 1000 x speed), so players could not fill their merchants.
Raise the cap to maxlength="9" (~1 billion), which covers any server speed.
The server already validates against available resources and merchant capacity,
so no server-side change is needed and no over-send is possible.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Templates/Build/17_edit.tpl

@@ -32,7 +32,7 @@ $deliveries = (int)($edited_route['deliveries']??1);
                         ];
                         foreach ($res as $r):?>
                             <img src="../../<?php echo GP_LOCATE;?>img/r/<?php echo $r[2];?>.gif" alt="<?php echo $r[3];?>" title="<?php echo $r[3];?>">
-                            <input class="text" type="text" name="<?php echo $r[0];?>" id="<?php echo $r[0];?>" value="<?php echo $r[1];?>" maxlength="5" tabindex="1" style="width:50px;">
+                            <input class="text" type="text" name="<?php echo $r[0];?>" id="<?php echo $r[0];?>" value="<?php echo $r[1];?>" maxlength="9" tabindex="1" style="width:50px;">
                         <?php endforeach;?>
                     </td>
                 </tr>