Add Oklab based color scheme "Ottosson" (#18502)

Campbell has been the default color scheme for a long time now,
but it has quite some issues with hue and chroma.

This PR introduces a new scheme which was created using the Oklab
color space to find colors with maximal distance to each other
and well distributed and consistent hue and chroma.
Because of this, I've named the scheme after the creator of Oklab.
 
Closes #17818

Author: lhecker

src/cascadia/TerminalSettingsModel/defaults.json

@@ -81,6 +81,29 @@
         //   - "foreground"
         //   - "background"
         //   - "cursorColor"
+        {
+            "name": "Ottosson",
+            "background": "#000000",
+            "foreground": "#bebebe",
+            "cursorColor": "#ffffff",
+            "selectionBackground": "#92a4fd",
+            "black": "#000000",
+            "red": "#be2c21",
+            "green": "#3fae3a",
+            "yellow": "#be9a4a",
+            "blue": "#204dbe",
+            "purple": "#bb54be",
+            "cyan": "#00a7b2",
+            "white": "#bebebe",
+            "brightBlack": "#808080",
+            "brightRed": "#ff3e30",
+            "brightGreen": "#58ea51",
+            "brightYellow": "#ffc944",
+            "brightBlue": "#2f6aff",
+            "brightPurple": "#fc74ff",
+            "brightCyan": "#00e1f0",
+            "brightWhite": "#ffffff"
+        },
         {
             "name": "Campbell",
             "foreground": "#CCCCCC",