feat(pack): Add pack for justfiles (#680)

lua/astrocommunity/pack/just/README.md

@@ -0,0 +1,5 @@
+# Just language pack
+
+This plugin does the following:
+
+- Adds `just` Treesitter parser: <https://github.com/IndianBoy42/tree-sitter-just>

lua/astrocommunity/pack/just/init.lua

@@ -0,0 +1,17 @@
+return {
+  "nvim-treesitter/nvim-treesitter",
+  optional = true,
+  dependencies = {
+    {
+      "IndianBoy42/tree-sitter-just",
+      config = function()
+        require("nvim-treesitter.parsers").get_parser_configs().just = {
+          install_info = { url = vim.fn.stdpath "data" .. "/lazy/tree-sitter-just", files = { "src/parser.c" } },
+          files = { "src/parser.c", "src/scanner.cc" },
+          branch = "main",
+          -- use_makefile = true -- this may be necessary on MacOS (try if you see compiler errors)
+        }
+      end,
+    },
+  },
+}