## Why

`group_vars/*.yml` files contain user-specific configuration (domain names, email, port/cipher preferences). Like the inventory, they should be `.example` templates in git with the actual files gitignored.

## What Changes

- Rename `group_vars/{all,relay,landing}.yml` to `.yml.example` via git mv
- Add `group_vars/*.yml` (excluding `.example`) to `.gitignore`
- Update README to document the copy step

## Capabilities

### New Capabilities

(none)

### Modified Capabilities

(none — this is a file organization change, not a behavior change)

## Impact

- `group_vars/*.yml` gitignored
- `group_vars/*.yml.example` committed as templates
- README updated