Naming, layout and comments: descriptive full-word names, one item per line in wrapped calls and literals, and doc comments on exported names

Short and single-letter names in application code become full words (tests
keep theirs). Wrapped calls, signatures and composite literals put one item
per line, and one-line function bodies are expanded. Exported names and
groups of constants get doc comments, and comments refer to the renamed
identifiers.

internal/util/worker.go

@@ -135,26 +135,29 @@ func (w Worker) execute(
 	}
 }
 
-// AwaitTask runs fn in its own goroutine and returns its result, or ctx.Err()
+// AwaitTask runs task in its own goroutine and returns its result, or ctx.Err()
 // if ctx is cancelled first. This lets a Task stop waiting on a call that does
 // not respond promptly to cancellation.
 //
 // The result channel is buffered, so if ctx wins the race the goroutine can
 // still deliver its result and exit instead of blocking forever.
-func AwaitTask[T any](ctx context.Context, fn func() (T, error)) (T, error) {
+func AwaitTask[T any](ctx context.Context, task func() (T, error)) (T, error) {
 	type result struct {
 		val T
 		err error
 	}
-	ch := make(chan result, 1)
+	results := make(chan result, 1)
 	go func() {
-		val, err := fn()
-		ch <- result{val, err}
+		value, err := task()
+		results <- result{
+			val: value,
+			err: err,
+		}
 	}()
 
 	select {
-	case r := <-ch:
-		return r.val, r.err
+	case result := <-results:
+		return result.val, result.err
 	case <-ctx.Done():
 		var zero T
 		return zero, ctx.Err()
@@ -162,15 +165,15 @@ func AwaitTask[T any](ctx context.Context, fn func() (T, error)) (T, error) {
 }
 
 // AwaitTaskE is AwaitTask for a function that returns only an error.
-func AwaitTaskE(ctx context.Context, fn func() error) error {
-	ch := make(chan error, 1)
+func AwaitTaskE(ctx context.Context, task func() error) error {
+	results := make(chan error, 1)
 	go func() {
-		err := fn()
-		ch <- err
+		err := task()
+		results <- err
 	}()
 
 	select {
-	case err := <-ch:
+	case err := <-results:
 		return err
 	case <-ctx.Done():
 		return ctx.Err()