fix(build): complete strict lint and test cleanup (replacement for #476)

src/providers/reliable.rs

@@ -412,10 +412,7 @@ impl Provider for ReliableProvider {
 
             // Convert channel receiver to stream
             return stream::unfold(rx, |mut rx| async move {
-                match rx.recv().await {
-                    Some(chunk) => Some((chunk, rx)),
-                    None => None,
-                }
+                rx.recv().await.map(|chunk| (chunk, rx))
             })
             .boxed();
         }

src/providers/traits.rs

@@ -140,7 +140,7 @@ impl StreamChunk {
 
     /// Estimate tokens (rough approximation: ~4 chars per token).
     pub fn with_token_estimate(mut self) -> Self {
-        self.token_count = (self.delta.len() + 3) / 4;
+        self.token_count = self.delta.len().div_ceil(4);
         self
     }
 }