Update EncodeJson in redbean to ignore useoutput outside of request handling

tool/net/help.txt

@@ -508,10 +508,15 @@ FUNCTIONS
            encodebase64.c.
 
    EncodeJson(value[,options:table]) → json:str
-           Turns passed Lua value into a JSON string. The following options
+           Turns passed Lua value into a JSON string. Tables with non-zero
-           can be used:
+           length (as reported by `#`) are encoded as arrays with non-array
+           elements ignored. Empty tables are encoded as empty arrays. All
+           other tables are encoded as objects with numerical keys
+           converted to strings (so `{[3]=1}` is encoded as `{"3":1}`).
+           The following options can be used:
              - useoutput: (bool=false) encodes the result directly to the
-               output buffer and returns `nil` value.
+               output buffer and returns `nil` value. This option is
+               ignored if used outside of request handling code.
              - numformat: (string="%.14g") sets numeric format to be used.
              - maxdepth: (number=64) sets the max number of nested tables.
 

tool/net/redbean.c

@@ -4764,7 +4764,8 @@ static int LuaEncodeJson(lua_State *L) {
   if (lua_istable(L, 2)) {
     lua_settop(L, 2);  // discard any extra arguments
     lua_getfield(L, 2, "useoutput");
-    if (lua_isboolean(L, -1)) useoutput = lua_toboolean(L, -1);
+    // ignore useoutput outside of request handling
+    if (ishandlingrequest && lua_isboolean(L, -1)) useoutput = lua_toboolean(L, -1);
     lua_getfield(L, 2, "maxdepth");
     maxdepth = luaL_optinteger(L, -1, maxdepth);
     lua_getfield(L, 2, "numformat");