[FEATURE] Allow opening terminal without automatically entering insert mode

## Feature Description
I would like an option where when I move my cursor to the terminal, it doesn't automatically enters terminal mode but stays in normal mode

## Use Case

I move around a lot and it always trips me up when my navigation buttons do not work anymor because they are trapped by the terminal in neovim.

## Proposed Solution

I tried passing these options, I have also set for the snacks terminal, where they work as expected.
It would nice if it would respect those options by default if they are configured in snacks terminal or pass them like this.

```lua
---@type LazySpec
return {
"coder/claudecode.nvim",
dependencies = { "folke/snacks.nvim" },
opts = {
terminal = {
provider = "snacks",
snacks_win_opts = {
start_insert = true,
auto_insert = false,
auto_close = true,
},
},
},
keys = {
{ "ac", "ClaudeCode", desc = "Toggle Claude Code" },
{ "as", "ClaudeCodeSend", mode = "v", desc = "Send to Claude Code" },
{ "ast", "ClaudeCodeStatus", desc = "Claude Code Status" },
},
}
```

まず、ターミナルプロバイダーがフォーカスと挿入モードの動作をどのように処理しているかを追跡し、次に要求された terminal.snacks_win_opts の値を既存の snacks 統合と比較します。設定されたターミナルオプションが尊重される状態で、ターミナルを開いたりフォーカスしたりしてもノーマルモードのままでいられれば完了です。

索引モデルが issue の本文から書いたものです。