fix(clippy): replace expect() with let-else pattern in kernel tests

Signed-off-by: StreamKit Devin <devin@streamkit.dev>
Co-Authored-By: Claudio Costa <cstcld91@gmail.com>

Author: streamkit-devin

crates/nodes/src/video/compositor/kernel.rs

@@ -523,7 +523,9 @@ mod tests {
         // crop_y=0.6 → raw y = round(0.6 * 5) = 3 (odd).
         // For I420 the origin must be rounded down to even: (2, 2).
         let result = compute_src_crop(10, 10, 0.6, 0.6, 2.0, PixelFormat::I420);
-        let (x, y, w, h) = result.expect("I420 crop should succeed");
+        let Some((x, y, w, h)) = result else {
+            panic!("I420 crop should return Some");
+        };
         assert_eq!(x % 2, 0, "I420 crop x must be even, got {x}");
         assert_eq!(y % 2, 0, "I420 crop y must be even, got {y}");
         assert_eq!(w, 5);
@@ -534,7 +536,9 @@ mod tests {
     fn compute_src_crop_aligns_odd_origin_for_nv12() {
         // Same geometry as above but with NV12.
         let result = compute_src_crop(10, 10, 0.6, 0.6, 2.0, PixelFormat::Nv12);
-        let (x, y, w, h) = result.expect("NV12 crop should succeed");
+        let Some((x, y, w, h)) = result else {
+            panic!("NV12 crop should return Some");
+        };
         assert_eq!(x % 2, 0, "NV12 crop x must be even, got {x}");
         assert_eq!(y % 2, 0, "NV12 crop y must be even, got {y}");
         assert_eq!(w, 5);
@@ -545,7 +549,9 @@ mod tests {
     fn compute_src_crop_preserves_odd_origin_for_rgba() {
         // For RGBA8 there is no chroma subsampling — odd origins are fine.
         let result = compute_src_crop(10, 10, 0.6, 0.6, 2.0, PixelFormat::Rgba8);
-        let (x, y, _, _) = result.expect("RGBA crop should succeed");
+        let Some((x, y, _, _)) = result else {
+            panic!("RGBA crop should return Some");
+        };
         assert_eq!(x, 3, "RGBA crop x should remain 3 (odd is fine)");
         assert_eq!(y, 3, "RGBA crop y should remain 3 (odd is fine)");
     }
@@ -555,7 +561,9 @@ mod tests {
         // When the raw origin is already even, alignment is a no-op.
         // crop_x=0.0 → x = 0 (even), crop_y=0.0 → y = 0 (even).
         let result = compute_src_crop(10, 10, 0.0, 0.0, 2.0, PixelFormat::I420);
-        let (x, y, _, _) = result.expect("I420 even-origin crop should succeed");
+        let Some((x, y, _, _)) = result else {
+            panic!("I420 even-origin crop should return Some");
+        };
         assert_eq!(x, 0);
         assert_eq!(y, 0);
     }