Refactor main loop touch flow and update docs

lib/input_manager.h

@@ -37,9 +37,9 @@ public:
     InputManager(LowLevelTouch* touch, const GameConfig* config);
     
     /**
-     * @brief Process touch input from controller
-     * @param last_time Pointer to last touch timestamp for debouncing
-     * @return InputEvent (valid=false if no valid input)
+     * @brief Process touch input using hybrid IRQ + active-session sampling.
+     * @param last_time Pointer to last touch timestamp (0 means no active touch session)
+     * @return InputEvent (valid=false if no state change/update is emitted)
      */
     InputEvent process_touch_input(uint32_t* last_time);
     
@@ -97,6 +97,8 @@ public:
 private:
     LowLevelTouch* touch;
     const GameConfig* config;
+    // Consecutive touch_count==0 samples while a touch session is active.
+    // Used to suppress false TOUCH_UP events from transient touch controller jitter.
     uint8_t no_touch_samples = 0;
     
     // Virtual button regions