feat(ncurses): Add interaction callbacks and improve input handling

Introduces Input Processing and Interaction helpers for the Ncurses renderer, ensuring robust mouse support and simplified event handling.

**Renderer (`renderers/ncurses`):**
- **`Clay_Ncurses_ProcessInput`**: Added a dedicated input processing function that handles both keyboard and mouse events.
  - Implemented persistent `_isMouseDown` state tracking to fix missed "fast clicks" and preserve button state during drag operations.
  - Adjusted `mousemask` to `BUTTON1_PRESSED | BUTTON1_RELEASED | REPORT_MOUSE_POSITION` to bypass Ncurses' internal click resolution delay.
- **`Clay_Ncurses_OnClick`**: Added a helper function to easily attach click listeners.
  - Registers the user's callback directly via `Clay_OnHover` (avoiding allocation/proxies).
  - Matches the standard Clay callback signature pattern.

**Example (`examples/ncurses-example`):**
- **Input Loop**: Migrated main loop to use `Clay_Ncurses_ProcessInput`.
- **Interactions**:
  - Added a "Toggle Help" button to the sidebar.
  - Implemented `HandleHelpToggleClick` callback, which explicitly checks for `CLAY_POINTER_DATA_RELEASED_THIS_FRAME` to validate clicks.
  - Added visual hover effects to sidebar items.

**Documentation (`renderers/ncurses/README.md`):**
- Updated "Usage" section to demonstrate `Clay_Ncurses_ProcessInput`.
- Added "Input & Interaction" section documenting the new helpers.

renderers/ncurses/clay_renderer_ncurses.c

@@ -425,7 +425,10 @@ void Clay_Ncurses_Initialize() {
     keypad(stdscr, TRUE);
     curs_set(0);
 
-    mousemask(ALL_MOUSE_EVENTS | REPORT_MOUSE_POSITION, NULL);
+    // We only ask for PRESS and RELEASE events.
+    // If we ask for CLICK events, ncurses waits to see if a release happens quickly,
+    // which delays the report of the PRESS event or swallows it, causing Clay to miss the "Down" state.
+    mousemask(BUTTON1_PRESSED | BUTTON1_RELEASED | REPORT_MOUSE_POSITION, NULL);
 
     start_color();
     use_default_colors();
@@ -613,3 +616,58 @@ static int Clay_Ncurses_MeasureStringWidth(Clay_StringSlice text) {
     }
     return width;
 }
+
+/**
+ * @brief Handles Ncurses input and updates Clay's internal pointer state.
+ * Use this instead of standard getch() in your main loop to enable mouse interaction.
+ * 
+ * @param window The Ncurses window to read input from (e.g. stdscr).
+ * @return The key code pressed, or ERR if no input.
+ */
+static bool _pointerReleasedThisFrame = false;
+
+int Clay_Ncurses_ProcessInput(WINDOW *window) {
+    int key = wgetch(window);
+    _pointerReleasedThisFrame = false;
+
+    // Handle Mouse
+    if (key == KEY_MOUSE) {
+        MEVENT event;
+        if (getmouse(&event) == OK) {
+            // Convert Cell Coordinates -> Clay Logical Coordinates
+            Clay_Vector2 mousePos = { 
+                (float)event.x * CLAY_NCURSES_CELL_WIDTH, 
+                (float)event.y * CLAY_NCURSES_CELL_HEIGHT 
+            };
+
+            // Persistent state to handle drag/move events where button state might be absent in the event mask
+            static bool _isMouseDown = false;
+
+            if (event.bstate & (BUTTON1_PRESSED | BUTTON1_DOUBLE_CLICKED | BUTTON1_TRIPLE_CLICKED)) {
+                _isMouseDown = true;
+            }
+
+            if (event.bstate & BUTTON1_RELEASED) {
+                _isMouseDown = false;
+            }
+
+            // Update Clay State
+            Clay_SetPointerState(mousePos, _isMouseDown);
+        }
+    }
+
+    return key;
+}
+
+/**
+ * @brief Helper to attach an OnClick listener to the current element.
+ * Registers a hover callback. The user's function must check `pointerData.state == CLAY_POINTER_DATA_RELEASED_THIS_FRAME`.
+ * 
+ * @param onClickFunc Function pointer to call.
+ * @param userData User data passed to the callback.
+ */
+void Clay_Ncurses_OnClick(void (*onClickFunc)(Clay_ElementId elementId, Clay_PointerData pointerData, void *userData), void *userData) {
+    if (onClickFunc) {
+        Clay_OnHover(onClickFunc, userData);
+    }
+}