Remove tmux-workspaces in favor of tmuxinator-only workflow

- Delete tmux-workspaces.zsh and .tmux-templates directory
- Remove TW_* config settings from dotfiles.conf
- Clean up tmuxinator.zsh (remove import/integration code)
- Update README, INSTALL, and REFERENCE docs
- Fix editor config: .zshrc now uses DEFAULT_EDITOR from dotfiles.conf

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

docs/REFERENCE.md

@@ -499,14 +499,6 @@ Systemd service management.
 
 **Aliases:** `scs`, `scstart`, `scstop`, `screload`, `scmask`, `scunmask`, `jctl`, `jctlf`, `jctlb`, `jctlerr`
 
-### tmux-workspaces.zsh
-
-Tmux workspace management.
-
-**Exported functions:** `tw`, `tw-create`, `tw-attach`, `tw-list`, `tw-delete`, `tw-save`, `tw-templates`, `tw-template-edit`, `tw-sync`, `tw-rename`, `twf`
-
-**Aliases:** `twl`, `twc`, `twa`, `twd`, `tws`, `twt`, `twe`
-
 ---
 
 ## Color Reference