feat(plugins): replace NeoCodeium with Supermaven and add Supermaven plugins

lua/plugins/supermaven.lua

@@ -0,0 +1,44 @@
+-- Disable supermaven in buffers under the LeetCode work directory, and
+-- re-enable it when leaving them.
+--
+-- Note: supermaven's built-in `condition` option is one-way — its BufEnter
+-- listener gates the restart branch on `vim.g.SUPERMAVEN_DISABLED`, which
+-- `api.stop()` itself sets, so once auto-stopped it never comes back. This
+-- autocmd owns both directions instead. `vim.g.supermaven_leetcode_stopped`
+-- distinguishes our auto-stop from a manual :SupermavenStop, which stays off.
+local leetcode_dir = vim.fn.expand "~/Developer/github.com/prdlk/leetcode/work/"
+
+local function is_leetcode_buffer()
+  local name = vim.api.nvim_buf_get_name(0)
+  return name:sub(1, #leetcode_dir) == leetcode_dir
+end
+
+local function sync()
+  local api = require "supermaven-nvim.api"
+  if is_leetcode_buffer() then
+    if api.is_running() then
+      api.stop()
+      vim.g.supermaven_leetcode_stopped = true
+    end
+  elseif vim.g.supermaven_leetcode_stopped and not api.is_running() then
+    vim.g.supermaven_leetcode_stopped = nil
+    api.start()
+  end
+end
+
+return {
+  "supermaven-inc/supermaven-nvim",
+  optional = true,
+  -- ignore_filetypes gates both the buffer sync (on_update) and the
+  -- suggestion poll, so python buffers are never sent to the binary
+  opts = { ignore_filetypes = { python = true } },
+  config = function(_, opts)
+    require("supermaven-nvim").setup(opts)
+    vim.api.nvim_create_autocmd("BufEnter", {
+      group = vim.api.nvim_create_augroup("supermaven_leetcode", { clear = true }),
+      desc = "Toggle supermaven off in LeetCode solution buffers",
+      callback = sync,
+    })
+    sync() -- plugin loads on VeryLazy; cover the buffer we're already sitting in
+  end,
+}