**New Structure:**
- getting-started/ - Quick start and first session guides
- configuration/ - YAML reference, layouts, lifecycle hooks
- workflow/ - Managing configs, local configs, session export
- reference/ - Complete CLI command reference

**New Pages:**
- getting-started/quick-start.md - Minimal getting started guide
- getting-started/your-first-session.md - Create first config walkthrough
- configuration/yaml-reference.md - Complete field documentation
- configuration/layouts.md - Flexbox layouts, focus, zoom
- configuration/lifecycle.md - Startup/shutdown hooks and scripts
- workflow/managing-configs.md - Create, edit, validate, delete
- workflow/local-configs.md - Project .laio.yaml workflow
- workflow/session-export.md - Export sessions with caveats
- reference/cli-commands.md - All commands with examples

**Updated Pages:**
- basics.md - Streamlined with links to detailed sections
- advanced.md - Condensed with references to new pages

Improves navigation, reduces page length, better content organization.

The content from basics.md and advanced.md is now properly
distributed across focused pages:

- Command reference -> reference/cli-commands.md
- Config management -> workflow/managing-configs.md
- Local configs -> workflow/local-configs.md
- Session export -> workflow/session-export.md
- YAML examples -> configuration/yaml-reference.md
- Layouts -> configuration/layouts.md
- Known limitations -> reference/cli-commands.md
- Session switching -> reference/cli-commands.md

getting-started/ now contains only:
- installing.md - Installation instructions
- quick-start.md - Minimal getting started
- your-first-session.md - First config walkthrough

This eliminates redundancy and creates a cleaner navigation structure.

Corrected the split terminology throughout documentation:

- Vertical split = split line runs vertically = panes side-by-side (left/right)
- Horizontal split = split line runs horizontally = panes stacked (top/bottom)

In laio (following CSS Flexbox convention):
- flex_direction: row → vertical split (side-by-side)
- flex_direction: column → horizontal split (stacked)

Previous docs incorrectly said "horizontal splits (panes side-by-side)"
which was contradictory. Now consistently describes splits by the
orientation of the split line itself.

Also corrected default from 'column' to 'row' based on code.

Added nushell shell completion support with installation example.
Nushell is supported via clap_complete_nushell dependency.

Changed nushell completion example to use proper nushell syntax
with pipe and 'save' command instead of bash redirect.

Moved nushell completion back into the main bash code block
with a comment noting it uses nushell syntax. Keeps examples
together and easier to read.

Use $env.HOME and path join instead of tilde expansion for
nushell completion example to follow nushell best practices.

Used sed to remove trailing whitespace from 5 documentation files
without altering content.

- Implement fix-whitespace git hook for staged files
- Integrate hook using gnused and shell script in pre-commit stage