feat(lua/config): add autocmd to mask .env values and toggle with <leader>ot

Adds autocmd to hide sensitive data in .env files on load and provides a toggle keymap (<leader>ot) to reveal original values.

New Features
- Mask .env file contents whenopened
- Toggle visibility with <leader>ot

lua/config/autocmd.lua

@@ -2,6 +2,65 @@ local function augroup(name)
     return vim.api.nvim_create_augroup('nvim' .. name, { clear = true })
 end
 
+-- hide sensetive data in .env
+local group = vim.api.nvim_create_augroup('EnvMask', { clear = true })
+local hidden = {}
+
+local function mask_line(line)
+    if line:match('^%s*#') or line:match('^%s*$') then
+        return line
+    end
+
+    local key, value = line:match('^([%w_]+)%s*=%s*(.*)')
+    if not key or not value then
+        return line
+    end
+
+    return key .. '=' .. string.rep('*', #value)
+end
+
+local function hide(buf)
+    if hidden[buf] then
+        return
+    end
+
+    local lines = vim.api.nvim_buf_get_lines(buf, 0, -1, false)
+    hidden[buf] = lines
+
+    local masked = {}
+    for i, line in ipairs(lines) do
+        masked[i] = mask_line(line)
+    end
+
+    vim.api.nvim_buf_set_lines(buf, 0, -1, false, masked)
+end
+
+local function show(buf)
+    if not hidden[buf] then
+        return
+    end
+    vim.api.nvim_buf_set_lines(buf, 0, -1, false, hidden[buf])
+    hidden[buf] = nil
+end
+
+vim.api.nvim_create_autocmd('BufReadPost', {
+    group = group,
+    pattern = { '.env', '.env.*', '*.env' },
+    callback = function(args)
+        vim.cmd('silent! noautocmd redraw')
+        hide(args.buf)
+    end,
+})
+
+vim.keymap.set('n', '<leader>ot', function()
+    local buf = vim.api.nvim_get_current_buf()
+    if hidden[buf] then
+        show(buf)
+    else
+        hide(buf)
+    end
+end, { desc = 'Toggle env masking' })
+
 -- Strip trailing spaces before write
 vim.api.nvim_create_autocmd({ 'BufWritePre' }, {
     group = augroup('strip_space'),