Settings Screen and first 2 settings (#18)

* white sleep screen

* quicker pwr button

* no extra spacing between paragraphs

* Added settings class with de/serialization and whiteSleepScreen setting to control inverting the sleep screen

* Added Settings screen for real, made settings a global singleton

* Added setting for extra paragraph spacing.

* fixed typo

* Rework after feedback

* Fixed type from bool to uint8

src/CrossPointSettings.h

@@ -0,0 +1,36 @@
+#pragma once
+#include <cstdint>
+#include <iosfwd>
+
+class CrossPointSettings {
+ private:
+  // Private constructor for singleton
+  CrossPointSettings() = default;
+
+  // Static instance
+  static CrossPointSettings instance;
+
+ public:
+  // Delete copy constructor and assignment
+  CrossPointSettings(const CrossPointSettings&) = delete;
+  CrossPointSettings& operator=(const CrossPointSettings&) = delete;
+
+  // Sleep screen settings
+  uint8_t whiteSleepScreen = 0;
+
+  // Text rendering settings
+  uint8_t extraParagraphSpacing = 1;
+
+  ~CrossPointSettings() = default;
+
+  // Get singleton instance
+  static CrossPointSettings& getInstance() {
+    return instance;
+  }
+
+  bool saveToFile() const;
+  bool loadFromFile();
+};
+
+// Helper macro to access settings
+#define SETTINGS CrossPointSettings::getInstance()