Implement semantic theme color system

config/omarchy/themed/alacritty.toml.tpl.sample

@@ -25,6 +25,10 @@
 #   {{ color0 }} through {{ color15 }} - Standard 16-color terminal palette
 #     color0-7:  Normal colors (black, red, green, yellow, blue, magenta, cyan, white)
 #     color8-15: Bright variants
+#   Semantic aliases are also available: {{ bg }}, {{ fg }}, {{ red }}, {{ green }},
+#   {{ yellow }}, {{ blue }}, {{ purple }}, {{ cyan }}, {{ muted }} and the
+#   {{ bright_* }} variants. The two forms are kept in sync by
+#   bin/omarchy-theme-set-templates.
 #
 # VARIABLE MODIFIERS:
 #   {{ variable_strip }} - Hex color without the # prefix (e.g., "1a1b26")
@@ -51,11 +55,11 @@ cursor = "{{ cursor }}"
 
 [colors.search.matches]
 foreground = "{{ background }}"
-background = "{{ color3 }}"
+background = "{{ yellow }}"
 
 [colors.search.focused_match]
 foreground = "{{ background }}"
-background = "{{ color1 }}"
+background = "{{ red }}"
 
 [colors.footer_bar]
 foreground = "{{ background }}"
@@ -66,21 +70,21 @@ text = "{{ selection_foreground }}"
 background = "{{ selection_background }}"
 
 [colors.normal]
-black = "{{ color0 }}"
-red = "{{ color1 }}"
-green = "{{ color2 }}"
-yellow = "{{ color3 }}"
-blue = "{{ color4 }}"
-magenta = "{{ color5 }}"
-cyan = "{{ color6 }}"
-white = "{{ color7 }}"
+black = "{{ bg }}"
+red = "{{ red }}"
+green = "{{ green }}"
+yellow = "{{ yellow }}"
+blue = "{{ blue }}"
+magenta = "{{ purple }}"
+cyan = "{{ cyan }}"
+white = "{{ fg }}"
 
 [colors.bright]
-black = "{{ color8 }}"
-red = "{{ color9 }}"
-green = "{{ color10 }}"
-yellow = "{{ color11 }}"
-blue = "{{ color12 }}"
-magenta = "{{ color13 }}"
-cyan = "{{ color14 }}"
-white = "{{ color15 }}"
+black = "{{ muted }}"
+red = "{{ bright_red }}"
+green = "{{ bright_green }}"
+yellow = "{{ bright_yellow }}"
+blue = "{{ bright_blue }}"
+magenta = "{{ bright_purple }}"
+cyan = "{{ bright_cyan }}"
+white = "{{ bright_fg }}"