affinity: as_chunks for the constant-size chunk loops (clippy 1.99 chunks_exact_to_as_chunks)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UHgFEHEsefoQoBParH47JA

crates/affinity/src/container.rs

@@ -337,9 +337,9 @@ fn unpredict(b: &mut [u8], compression: u8) -> Result<(), Error> {
         (0x40, _) => byte_delta(b),
         (0x80, false) => {
             let mut prev = 0u16;
-            for pair in b.chunks_exact_mut(2) {
-                let v = u16::from_le_bytes([pair[0], pair[1]]).wrapping_add(prev);
-                pair.copy_from_slice(&v.to_le_bytes());
+            for pair in b.as_chunks_mut::<2>().0.iter_mut() {
+                let v = u16::from_le_bytes(*pair).wrapping_add(prev);
+                *pair = v.to_le_bytes();
                 prev = v;
             }
         }
@@ -349,11 +349,11 @@ fn unpredict(b: &mut [u8], compression: u8) -> Result<(), Error> {
             if b.len() == 0x10000 {
                 let planes = b.to_vec();
                 let (hi, lo) = planes.split_at(0x8000);
-                for (i, out) in b.chunks_exact_mut(4).enumerate() {
+                for (i, out) in b.as_chunks_mut::<4>().0.iter_mut().enumerate() {
                     let (Some(h), Some(l)) = (hi.get(2 * i..2 * i + 2), lo.get(2 * i..2 * i + 2)) else {
                         return Err(Error::Malformed("tile size"));
                     };
-                    out.copy_from_slice(&[l[0], h[0], l[1], h[1]]);
+                    *out = [l[0], h[0], l[1], h[1]];
                 }
             }
         }

crates/affinity/src/paint.rs

@@ -129,7 +129,7 @@ const MAX_STOPS: usize = 1024;
 fn floats(v: &Value) -> Option<Vec<f64>> {
     match v {
         Value::Floats(f) => Some(f.clone()),
-        Value::Bytes(b) if b.len() % 4 == 0 => Some(b.chunks_exact(4).map(|c| f64::from(f32::from_le_bytes([c[0], c[1], c[2], c[3]]))).collect()),
+        Value::Bytes(b) if b.len() % 4 == 0 => Some(b.as_chunks::<4>().0.iter().map(|c| f64::from(f32::from_le_bytes(*c))).collect()),
         _ => None,
     }
 }

crates/affinity/src/raster.rs

@@ -131,7 +131,7 @@ fn decode(r: &mut Reader, bitmap: ObjId, crop: (u32, u32, u32, u32), world: Affi
             f64::from(p.get(i).copied().unwrap_or(0)) / 255.0
         }
     };
-    for (i, px) in rgba.chunks_exact_mut(4).enumerate() {
+    for (i, px) in rgba.as_chunks_mut::<4>().0.iter_mut().enumerate() {
         let v: Vec<f64> = planes.iter().map(|p| sample(p, i)).collect();
         let (r2, g, b, a) = if channels == 1 {
             (v[0], v[0], v[0], 1.0)