feat: add minimal mode for reduced color palette

Add new `minimal` config option that provides a cleaner, more focused
  color scheme with fewer distinct colors:
  - Variables/constants: white
  - Functions/methods: blue
  - Types: aqua
  - Keywords/statements: gray
  - Operators: yellow
  - Brackets/punctuation: gray
  - Properties/members: violet

README.md

@@ -31,6 +31,7 @@
 - ⚡ Compilation to lua byte code for fast startup times
 - 🎨 Four beautiful theme variants to match your mood and environment
 - 🔆 Saturated mode for enhanced syntax highlighting visibility
+- 🎯 Minimal mode for a reduced color palette
 - 👁️ WCAG 2.1 AA compliant
 
 ## 📦 Installation
@@ -99,6 +100,7 @@ require('kanso').setup({
         light = "pearl"         -- try "zen", "mist" or "ink" !
     },
     foreground = "default",      -- "default" or "saturated" (can also be a table like background)
+    minimal = false,             -- reduced color palette for a more minimal look
 })
 
 -- setup must be called before loading
@@ -211,6 +213,43 @@ The saturation adjustment only affects syntax highlighting colors (strings, keyw
 
 </details>
 
+## 🎯 Minimal Mode
+
+Kansō supports a minimal mode that reduces the color palette for a cleaner, more focused coding experience. This mode uses fewer distinct colors while maintaining readability and visual hierarchy.
+
+<details>
+<summary><strong>🔳 Using Minimal Mode</strong></summary>
+
+Enable minimal mode in your configuration:
+
+```lua
+require('kanso').setup({
+    minimal = true,
+})
+```
+
+When enabled, the color scheme changes to:
+
+| Element | Color |
+|---------|-------|
+| Variables, Constants | White (foreground) |
+| Parameters | Gray |
+| Functions, Methods | Blue |
+| Types | Aqua |
+| Keywords, Statements | Gray |
+| Operators (`=`, `+`, `*`, etc.) | Yellow |
+| Brackets, Punctuation | Gray |
+| Properties, Members | Violet |
+| Strings | Green |
+| Numbers | Pink |
+
+This mode is ideal for:
+- Reducing visual noise while coding
+- Users who prefer a more monochromatic aesthetic
+- Minimizing distractions during focused work sessions
+
+</details>
+
 ## 🧰 Customization
 
 In Kansō, there are _two_ kinds of colors: `PaletteColors` and `ThemeColors`;