fix(jsonfly.lua): resolve function buf_request_all to work with new nvim

syntax and version changes not accounted for.
Refactored LSP request handling in jsonfly.lua to combine results from multiple LSP responses and handle empty results more gracefully. Improved code readability and maintainability by restructuring the nested if-else blocks.

Author: kletobias

Diff for: lua/telescope/_extensions/jsonfly.lua

@@ -196,27 +196,38 @@ return require("telescope").register_extension {
             if global_config.backend == "lsp" then
                 local params = vim.lsp.util.make_position_params(xopts.winnr)
 
-                vim.lsp.buf_request_all(
-                    current_buf,
-                    "textDocument/documentSymbol",
-                    params,
-                    function(response)
-                        if response == nil or #response == 0 then
-                            run_lua_parser()
-                            return
-                        end
-
-                        local result = response[1].result
+            vim.lsp.buf_request_all(
+                current_buf,
+                "textDocument/documentSymbol",
+                params,
+                function(results)
+                    if results == nil or vim.tbl_isempty(results) then
+                        run_lua_parser()
+                        return
+                    end
 
-                        local entries = parsers:get_entries_from_lsp_symbols(result)
+                    local combined_result = {}
 
-                        if allow_cache then
-                            cache:cache_buffer(current_buf, entries)
+                    for _, res in pairs(results) do
+                        if res.result then
+                            vim.list_extend(combined_result, res.result)
                         end
+                    end
+
+                    if vim.tbl_isempty(combined_result) then
+                        run_lua_parser()
+                        return
+                    end
+
+                    local entries = parsers:get_entries_from_lsp_symbols(combined_result)
 
-                        show_picker(entries, current_buf, xopts)
+                    if allow_cache then
+                        cache:cache_buffer(current_buf, entries)
                     end
-                )
+
+                    show_picker(entries, current_buf, xopts)
+                end
+            )
             else
                 run_lua_parser()
             end