### System details

- Omarchy 4.0.0-1 (Quattro stable), upgraded from a pre-Quattro installation
- Linux 7.1.8-arch1-3
- Intel Core Ultra 5 228V
- Intel Arc Graphics 130V/140V
- French/AZERTY keyboard layout

### What's wrong?

After upgrading an existing Omarchy installation to Quattro and rebooting, the Hyprland session uses the US/QWERTY layout instead of the previously configured French/AZERTY layout.

Before the upgrade, the active legacy config contained:

```conf
# ~/.config/hypr/input.conf
input {
  kb_layout = fr
  kb_options = compose:caps
}
```

The system console config contains:

```conf
# /etc/vconsole.conf
KEYMAP=fr
```

It does not contain `XKBLAYOUT`, which is valid: `vconsole.conf` only guarantees the console `KEYMAP` setting.

The Quattro upgrade leaves the legacy `input.conf` in place but switches Hyprland to the new Lua entry points. It always installs a stock `~/.config/hypr/input.lua`, and that file has no active keyboard-layout override. The packaged `default/hypr/input.lua` then does:

```lua
local kb_layout = vconsole.XKBLAYOUT or "us"
```

Because this installation has `KEYMAP=fr` but no `XKBLAYOUT`, the effective layout silently falls back to `us`. The migration `1781485962.sh` also sees the stock `input.lua` and leaves/replaces it with the packaged version, so the old `kb_layout = fr` is never carried over.

#### Steps to reproduce

1. Start with a pre-Quattro Omarchy installation where:
   - `~/.config/hypr/input.conf` contains `kb_layout = fr`
   - `/etc/vconsole.conf` contains only `KEYMAP=fr`
2. Upgrade to Quattro.
3. Reboot into the new Lua-based Hyprland configuration.
4. Type in any application.
5. Observe that the session uses US/QWERTY instead of French/AZERTY.

#### Expected behavior

The Quattro upgrade should preserve the explicitly configured keyboard layout from the legacy `input.conf`.

#### Actual behavior

The explicit legacy layout is ignored, and the new default falls back to `us`.

#### Workaround

Adding this to `~/.config/hypr/input.lua` restores the correct layout:

```lua
hl.config({
  input = {
    kb_layout = "fr",
  },
})
```

#### Suggested fix

During `omarchy-upgrade-to-quattro`, migrate active `kb_layout`, `kb_variant`, and `kb_options` values from the legacy `~/.config/hypr/input.conf` into the new `input.lua` before switching entry points. Alternatively, ensure the upgrade populates an appropriate `XKBLAYOUT` when only `KEYMAP` exists, while accounting for console/XKB naming differences.

A regression test could cover a legacy `input.conf` with `kb_layout = fr` plus a `vconsole.conf` containing only `KEYMAP=fr`.