feat: grlx LSP server in Go

LSP server for grlx recipe files (.grlx) providing:

- Completion for ingredients, methods, properties, requisite types,
  and step ID references
- Diagnostics for unknown ingredients/methods, missing required
  properties, unknown properties, and invalid requisite types
- Hover documentation for all ingredients and methods with property
  tables
- Full schema for all 6 grlx ingredients (cmd, file, group, pkg,
  service, user) with accurate properties from the grlx source

README.md

@@ -0,0 +1,91 @@
+# grlx-lsp
+
+Language Server Protocol (LSP) server for [grlx](https://github.com/gogrlx/grlx) recipe files (`.grlx`).
+
+## Features
+
+- **Completion** — ingredient.method names, property keys, requisite types, step ID references
+- **Diagnostics** — unknown ingredients/methods, missing required properties, unknown properties, invalid requisite types
+- **Hover** — documentation for ingredients, methods, properties, and requisite types
+
+## Installation
+
+```bash
+go install github.com/gogrlx/grlx-lsp/cmd/grlx-lsp@latest
+```
+
+## Editor Setup
+
+### Neovim (nvim-lspconfig)
+
+```lua
+vim.api.nvim_create_autocmd({"BufRead", "BufNewFile"}, {
+  pattern = "*.grlx",
+  callback = function()
+    vim.bo.filetype = "grlx"
+  end,
+})
+
+local lspconfig = require("lspconfig")
+local configs = require("lspconfig.configs")
+
+configs.grlx_lsp = {
+  default_config = {
+    cmd = { "grlx-lsp" },
+    filetypes = { "grlx" },
+    root_dir = lspconfig.util.find_git_ancestor,
+    settings = {},
+  },
+}
+
+lspconfig.grlx_lsp.setup({})
+```
+
+### VS Code
+
+Create `.vscode/settings.json`:
+
+```json
+{
+  "files.associations": {
+    "*.grlx": "yaml"
+  }
+}
+```
+
+Then configure a generic LSP client extension to run `grlx-lsp` for the `grlx` file type.
+
+## Supported Ingredients
+
+| Ingredient | Methods |
+|-----------|---------|
+| `cmd` | run |
+| `file` | absent, append, cached, contains, content, directory, exists, managed, missing, prepend, symlink, touch |
+| `group` | absent, exists, present |
+| `pkg` | cleaned, group_installed, held, installed, key_managed, latest, purged, removed, repo_managed |
+| `service` | disabled, enabled, masked, restarted, running, stopped, unmasked |
+| `user` | absent, exists, present |
+
+## Recipe Format
+
+grlx recipes are YAML files with Go template support:
+
+```yaml
+include:
+  - apache
+  - .dev
+
+steps:
+  install nginx:
+    pkg.installed:
+      - name: nginx
+  start nginx:
+    service.running:
+      - name: nginx
+      - requisites:
+        - require: install nginx
+```
+
+## License
+
+0BSD