Upgrade the NixOS `stateVersion` from 25.05 to 25.11 in all system configuration files and update all nix channel URLs to the 25.11 releases. Adjust Home Manager and terminal module configurations accordingly, clean up duplicated SSH keys, and update LLaMA server command lines. Minor housekeeping changes to package definitions and other configuration files are also included.
- Remove old code-companion-config.lua file
- Move LLM configuration to llm.lua with LlamaSwap and Copilot integration
- Add copilot-vim plugin to default.nix
- Update which-key bindings to include new CodeCompanion commands
- Configure CodeCompanion with chat, inline, and command strategies using LlamaSwap adapter
- Add memory configuration with default project files
- Update LSP configuration for CodeCompanion markdown rendering
