Add a Slovenian [si] layout

Part-of: <https://gitlab.gnome.org/World/Phosh/squeekboard/-/merge_requests/652>

data/keyboards/si.yaml

@@ -0,0 +1,121 @@
+---
+outlines:
+    default:          { width: 35.33, height: 52 }
+    subtle-highlight: { width: 35.33, height: 52 }
+    altline:          { width: 52.67, height: 52 }
+    wide:             { width: 52.67, height: 52 }
+    change-view:      { width: 52.67, height: 52 }
+    spaceline:        { width: 88.66, height: 52 }
+    special:          { width: 35.33, height: 52 }
+    placeholder:      { width: 35.33, height: 52 }
+
+views:
+    base:
+        - "q w e r t z u i o p"
+        - "a s d f g h j k l č"
+        - "Shift_L    y x c v b n m    BackSpace"
+        - "show_numbers show_accents preferences     space    , . Return"
+    upper:
+        - "Q W E R T Z U I O P"
+        - "A S D F G H J K L Č"
+        - "Shift_L    Y X C V B N M    BackSpace"
+        - "show_numbers show_upper_accents preferences     space    ! ? Return"
+    numbers:
+        - "1 2 3 4 5 6 7 8 9 0"
+        - "@ # $ % & - _ + ( )"
+        - "show_symbols    , \" ' : ; ! ?    BackSpace"
+        - "show_letters show_accents preferences     space    , . Return"
+    symbols:
+        - "~ ` | · √ π τ ÷ × ¶"
+        - "© ® £ € ¥ ^ ° * { }"
+        - "show_numbers    \\ / < > = [ ]    BackSpace"
+        - "show_letters show_accents preferences     space    § ¤ Return"
+    accents:
+        - "á é ẹ́  í ó ọ́  ú ŕ š đ"
+        - "ȃ ȇ ẹ̑  ȋ ȏ ọ̑  ȗ ȓ ć ž"
+        - "accents_Shift_L à è ì ò ù ö ü BackSpace"
+        - "show_letters show_accents preferences     space    ĺ ł Return"
+    upper_accents:
+        - "Á É Ẹ́  Í Ó Ọ́  Ú Ŕ Š Đ"
+        - "Ȃ Ȇ Ẹ̑  Ȋ Ȏ Ọ̑  Ȗ Ȓ Ć Ž"
+        - "accents_Shift_L À È Ì Ò Ù Ö Ü BackSpace"
+        - "show_letters show_upper_accents preferences     space    Ĺ Ł Return"
+
+buttons:
+    Shift_L:
+        action:
+            locking:
+                lock_view: "upper"
+                unlock_view: "base"
+        outline: "change-view"
+        icon: "key-shift"
+    accents_Shift_L:
+        action:
+            locking:
+                lock_view: "upper_accents"
+                unlock_view: "base"
+        outline: "change-view"
+        icon: "key-shift"
+    BackSpace:
+        outline: "altline"
+        icon: "edit-clear-symbolic"
+        action: "erase"
+    preferences:
+        action: "show_prefs"
+        outline: "special"
+        icon: "keyboard-mode-symbolic"
+    show_numbers:
+        action:
+            set_view: "numbers"
+        outline: "change-view"
+        label: "123"
+    show_letters:
+        action:
+            set_view: "base"
+        outline: "change-view"
+        label: "ABC"
+    show_symbols:
+        action:
+            set_view: "symbols"
+        outline: "change-view"
+        label: "*/="
+    show_accents:
+        action:
+            locking:
+                lock_view: "accents"
+                unlock_view: "base"
+        outline: "change-view"
+        label: "Ćž"
+    show_upper_accents:
+        action:
+            locking:
+                lock_view: "upper_accents"
+                unlock_view: "base"
+        outline: "change-view"
+        label: "Ćž"
+    space:
+        outline: "spaceline"
+        text: " "
+    Return:
+        outline: "wide"
+        icon: "key-enter"
+        keysym: "Return"
+    --:
+        outline: "placeholder"
+        text: ""
+    š:
+        outline: "subtle-highlight"
+    Š:
+        outline: "subtle-highlight"
+    ž:
+        outline: "subtle-highlight"
+    Ž:
+        outline: "subtle-highlight"
+    ć:
+        outline: "subtle-highlight"
+    Ć:
+        outline: "subtle-highlight"
+    đ:
+        outline: "subtle-highlight"
+    Đ:
+        outline: "subtle-highlight"