launch command: A new --bias option to adjust the size of newly created windows declaratively

Still need to implement it for the Grid layout.
Fixes #7634

docs/changelog.rst

@@ -76,6 +76,8 @@ Detailed list of changes
 
 - Add NERD fonts builtin so that users don't have to install them to use NERD symbols in kitty. The builtin font is used only if the symbols are not available in some system font
 
+- launch command: A new :option:`launch --bias` option to adjust the size of newly created windows declaratively (:iss:`7634`)
+
 - Sessions: A new command ``focus_matching_window`` to shift focus to a specific window, useful when creating complex layouts with splits (:disc:`7635`)
 
 - Wayland: Allow fractional scales less than one (:pull:`7549`)

docs/overview.rst

@@ -186,9 +186,8 @@ option in :file:`kitty.conf`. An example, showing all available commands:
     # Create the second column by splitting the first window vertically
     launch --location=vsplit
     # Create the third window in the second column by splitting the second window horizontally
-    launch --location=hsplit
-    # Make the third window shorter so that the split is not even
-    resize_window shorter 5
+    # Make it take 40% of the height instead of 50%
+    launch --location=hsplit --bias=40
     # Go back to focusing the first window, so that we can split it
     focus_matching_window var:window=first
     # Create the final window in the first column