patch: treesitter highlighting, lsp inlay hints and update flake (#20)

Small update to enable Treesitter highlighting by default, enable LSP
inlay hints and update flake inputs to the latest version

config/plugins/editor/treesitter.nix

@@ -3,6 +3,7 @@
     enable = true;
     settings = {
       indent.enable = true;
+      highlight.enable = true;
     };
     folding = false;
     nixvimInjections = true;

config/plugins/lsp/lsp.nix

@@ -5,6 +5,7 @@
     helm = {enable = true;};
     lsp = {
       enable = true;
+      inlayHints = true;
       servers = {
         html = {enable = true;};
         lua-ls = {enable = true;};