Document keyboard remap (AltGr+P → apostrophe), add Kara and Mouse Tiler to software list

cachy-overview.md

@@ -1,6 +1,6 @@
 # Main Desktop — CachyOS Overview
 
-> Last updated: 2026-05-27
+> Last updated: 2026-06-11
 
 ---
 
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 | **AUR Helper** | paru 2.1 |
 | **Automation** | n8n (on homelab) |
 | **Theming** | CachyOS Nord KDE, CachyOS Emerald KDE, CachyOS Iridescent KDE |
+| **KWin Scripts** | Mouse Tiler |
+| **Productivity** | Kara |
 
 ### Compilers
 
@@ -168,3 +170,35 @@
 | **NVIDIA module** | linux-cachyos-nvidia-open 7.0.10 |
 | **Bootloader** | Limine 12.3 |
 | **Intel microcode** | 20260512 |
+
+---
+
+## Keyboard Customisation
+
+### AltGr+P → `'` (apostrophe) remap
+
+The default Slovak (`sk`) xkb layout inherits `þ` on AltGr+P from the `latin` include. Fixed via a custom xkb user variant.
+
+**Files:**
+
+- `~/.config/xkb/symbols/sk` — custom variant file (named `sk`, not `sk_custom`, because libxkbcommon looks up variants by layout filename)
+- `~/.config/xkb/rules/evdev.xml` — local copy of system evdev.xml with `sk_custom` variant registered
+- `~/.config/xkb/rules/evdev` — local copy of system evdev rules file
+- `~/.config/kxkbrc` — KDE keyboard config pointing to `LayoutList=sk`, `VariantList=sk_custom`
+
+**`~/.config/xkb/symbols/sk` content:**
+
+```
+partial alphanumeric_keys
+xkb_symbols "sk_custom" {
+    include "sk(basic)"
+    key <AD10> { [ p, P, apostrophe, NoSymbol ] };
+};
+```
+
+**Gotchas:**
+- `setxkbmap` and `XKB_CONFIG_ROOT` do not work on Wayland — changes must go through `~/.config/xkb/`
+- The symbols file must be named after the layout (`sk`), not the variant (`sk_custom`) — libxkbcommon looks up variants inside the layout file
+- `include "sk"` causes infinite recursion when the file is named `sk` — use `include "sk(basic)"` instead
+- KDE reads `~/.config/xkb/`, not `~/.xkb/`
+- keyd was tested but doesn't work cleanly with non-US layouts on Wayland without switching the display server to US layout