feat: add neovim pager support and refactor into modular architecture

[TunaCuma]

Summary

This PR adds neovim/vim as supported pagers and refactors the codebase into a modular architecture for easier extensibility.

Changes

Neovim Pager Support

• Add neovim/vim as supported pagers using :Man command
• Implement vim-compatible search patterns that match option definitions
• Use nvim +"Man <cmd>" +only +/<pattern> format for proper integration
• Fix terminal access issues with plugins like image.nvim

Modular Architecture

Refactored the monolithic zsh-vi-man.zsh into logical layers:

lib/
├── parser.zsh      # Word and command parsing (49 lines)
├── pattern.zsh     # Search pattern builders for less/nvim (93 lines)
├── pager.zsh       # Pager-specific logic (85 lines)
└── keybinding.zsh  # Keybinding management (50 lines)

Benefits:

• Easy to add new pagers (add functions to lib/pager.zsh)
• Easy to add shell environments (modify lib/keybinding.zsh)
• Separate pattern logic for each pager type
• Still lightweight (~340 total lines)

Testing

• Added test_nvim.zsh with 46 comprehensive tests for neovim patterns
• Updated CI workflow to run neovim tests
• Updated Makefile with test-nvim target
• All 101 tests pass (55 less + 46 nvim)

False Positive Prevention

• Nvim patterns now only match options at line start (after whitespace)
• Prevents matching options mentioned in description text like:
  • -f ...has no effect on the -d, -l, -R...
  • -@ ...in long (-l) output.

Testing Done

make test-all  # All tests pass

Manual testing with:

• ls -la → finds -l, press n for -a
• git commit -m → opens git-commit man page
• tree | grep -r → opens grep man (not tree)

Fixes

Fixes #4