feat: add first-class Neovim support with enhanced formatting

- Add modern Lua implementation with modular architecture
- Implement HEREDOC preservation and smart comment indentation
- Create dual implementation (Neovim Lua + VimScript fallback)
- Add comprehensive health check and configuration system
- Enhance formatting engine with state machine for context awareness
- Update documentation with Lua configuration examples
- Add memory files for development workflow and conventions

lua/shellspec/autocmds.lua

@@ -0,0 +1,102 @@
+-- Neovim-native autocommands for ShellSpec
+local config = require("shellspec.config")
+local format = require("shellspec.format")
+local M = {}
+
+-- Autocommand group
+local augroup = vim.api.nvim_create_augroup("ShellSpec", { clear = true })
+
+-- Setup buffer-local settings
+local function setup_buffer(bufnr)
+  -- Set buffer options
+  vim.api.nvim_set_option_value("commentstring", "# %s", { buf = bufnr })
+  vim.api.nvim_set_option_value("foldmethod", "indent", { buf = bufnr })
+  vim.api.nvim_set_option_value("shiftwidth", config.get("indent_size"), { buf = bufnr })
+  vim.api.nvim_set_option_value("tabstop", config.get("indent_size"), { buf = bufnr })
+  vim.api.nvim_set_option_value("expandtab", config.get("use_spaces"), { buf = bufnr })
+
+  -- Buffer-local commands
+  vim.api.nvim_buf_create_user_command(bufnr, "ShellSpecFormat", function()
+    format.format_buffer(bufnr)
+  end, { desc = "Format ShellSpec buffer" })
+
+  vim.api.nvim_buf_create_user_command(bufnr, "ShellSpecFormatRange", function(opts)
+    format.format_selection(bufnr, opts.line1, opts.line2)
+  end, {
+    range = true,
+    desc = "Format ShellSpec selection",
+  })
+
+  -- Optional: Set up LSP-style formatting
+  if vim.fn.has("nvim-0.8") == 1 then
+    vim.api.nvim_buf_set_option(bufnr, "formatexpr", 'v:lua.require("shellspec.format").format_buffer()')
+  end
+end
+
+-- Create all autocommands
+function M.setup()
+  -- FileType detection and setup
+  vim.api.nvim_create_autocmd("FileType", {
+    group = augroup,
+    pattern = "shellspec",
+    callback = function(args)
+      setup_buffer(args.buf)
+    end,
+    desc = "Setup ShellSpec buffer",
+  })
+
+  -- Auto-format on save (if enabled)
+  if config.get("auto_format") then
+    vim.api.nvim_create_autocmd("BufWritePre", {
+      group = augroup,
+      pattern = { "*.spec.sh", "*_spec.sh" },
+      callback = function(args)
+        -- Only format if it's a shellspec buffer
+        local filetype = vim.api.nvim_get_option_value("filetype", { buf = args.buf })
+        if filetype == "shellspec" then
+          format.format_buffer(args.buf)
+        end
+      end,
+      desc = "Auto-format ShellSpec files on save",
+    })
+  end
+
+  -- Enhanced filetype detection with better patterns
+  vim.api.nvim_create_autocmd({ "BufRead", "BufNewFile" }, {
+    group = augroup,
+    pattern = {
+      "*_spec.sh",
+      "*.spec.sh",
+      "spec/*.sh",
+      "test/*.sh",
+    },
+    callback = function(args)
+      -- Set filetype to shellspec
+      vim.api.nvim_set_option_value("filetype", "shellspec", { buf = args.buf })
+    end,
+    desc = "Detect ShellSpec files",
+  })
+
+  -- Additional pattern for nested spec directories
+  vim.api.nvim_create_autocmd({ "BufRead", "BufNewFile" }, {
+    group = augroup,
+    pattern = "**/spec/**/*.sh",
+    callback = function(args)
+      vim.api.nvim_set_option_value("filetype", "shellspec", { buf = args.buf })
+    end,
+    desc = "Detect ShellSpec files in nested spec directories",
+  })
+end
+
+-- Cleanup function
+function M.cleanup()
+  vim.api.nvim_clear_autocmds({ group = augroup })
+end
+
+-- Update configuration and refresh autocommands
+function M.refresh()
+  M.cleanup()
+  M.setup()
+end
+
+return M