Theran Slinkard

Results 2 issues of Theran Slinkard

**Describe the bug** Chunk and line_num fail to get the correct treesitter node, only the outermost scope is highlighted. with use_treesitter = false both work as intended. Indent seems unaffected...

I found a typo in the function checking for single mappings, you were checking type(nx_map[1] == "string") instead of type(nx_map[1]) == "string".