[FEATURE] Start headless Claude integration

[makcakaya]

Feature Description

ac starts the integration and also creates a split window for Claude. This split window is the most preferable for everyone. A headless mode, which just starts the integration without the split, allowing the user to integration Neovim and an external Claude process is desirable.

Use Case

For people who prefer working with Claude outside Neovim, the headless mode is better. User can fire up Neovim and Claude from completely different terminals/windows/processes and everything still works.

Proposed Solution

Although I didn't check the code yet, I think the solution is just to skip creating the split in headless mode, and create a way to configure a keybinding for the headless mode.

Alternatives Considered

Have you considered any alternative solutions or workarounds?

Additional Context

Add any other context, screenshots, or examples about the feature request here.

[ThomasK33]

:ClaudeCodeStart

[robertfall]

I set this up as a workaround for #53 but running :ClaudeCodeStart on a fresh nvim instance gives me a warning

[ClaudeCode] [init] [WARN] Claude Code integration is already running on port 44526

It does appear to work though.