add uniffi CP437Grid, equals

add equals method

add uniffi copy_raw method

crates/servicepoint_binding_uniffi/src/brightness_grid.rs

@@ -1,4 +1,4 @@
-use servicepoint::{Brightness, Grid};
+use servicepoint::{Brightness, DataRef, Grid};
 use std::sync::{Arc, RwLock};
 
 #[derive(uniffi::Object)]
@@ -67,4 +67,14 @@ impl BrightnessGrid {
     pub fn height(&self) -> u64 {
         self.actual.read().unwrap().height() as u64
     }
+
+    pub fn equals(&self, other: &BrightnessGrid) -> bool {
+        let a = self.actual.read().unwrap();
+        let b = other.actual.read().unwrap();
+        *a == *b
+    }
+
+    pub fn copy_raw(&self) -> Vec<u8> {
+        self.actual.read().unwrap().data_ref().iter().map(u8::from).collect()
+    }
 }