update bls12_381 documentation formatting using warning box

Author: leighmcculloch

soroban-sdk/src/crypto/bls12_381.rs

@@ -208,14 +208,15 @@ impl Fp {
     /// Maps this `Fp` element to a `G1Affine` point using the [simplified SWU
     /// mapping](https://www.rfc-editor.org/rfc/rfc9380.html#name-simplified-swu-for-ab-0).
     ///
-    /// **Important:** The resulting point is on the curve but may not be in the
-    /// prime-order subgroup (operations like pairing may fail). To ensure the
-    /// point is in the prime-order subgroup, cofactor clearing must be
-    /// performed on the output.
+    /// <div class="warning">
+    /// <h6>Warning</h6>
+    /// The resulting point is on the curve but may not be in the prime-order subgroup (operations
+    /// like pairing may fail). To ensure the point is in the prime-order subgroup, cofactor
+    /// clearing must be performed on the output.
     ///
-    /// For applications requiring a point directly in the prime-order subgroup,
-    /// consider using `hash_to_g1`, which handles subgroup checks and cofactor
-    /// clearing internally.
+    /// For applications requiring a point directly in the prime-order subgroup, consider using
+    /// `hash_to_g1`, which handles subgroup checks and cofactor clearing internally.
+    /// </div>
     pub fn map_to_g1(&self) -> G1Affine {
         self.env().crypto().bls12_381().map_fp_to_g1(self)
     }
@@ -344,14 +345,15 @@ impl Fp2 {
     /// Maps this `Fp2` element to a `G2Affine` point using the [simplified SWU
     /// mapping](https://www.rfc-editor.org/rfc/rfc9380.html#name-simplified-swu-for-ab-0).
     ///
-    /// **Important:** The resulting point is on the curve but may not be in the
-    /// prime-order subgroup (operations like pairing may fail). To ensure the
-    /// point is in the prime-order subgroup, cofactor clearing must be
-    /// performed on the output.
+    /// <div class="warning">
+    /// <h6>Warning</h6>
+    /// The resulting point is on the curve but may not be in the prime-order subgroup (operations
+    /// like pairing may fail). To ensure the point is in the prime-order subgroup, cofactor
+    /// clearing must be performed on the output.
     ///
-    /// For applications requiring a point directly in the prime-order subgroup,
-    /// consider using `hash_to_g2`, which handles subgroup checks and cofactor
-    /// clearing internally.
+    /// For applications requiring a point directly in the prime-order subgroup, consider using
+    /// `hash_to_g2`, which handles subgroup checks and cofactor clearing internally.
+    /// </div>
     pub fn map_to_g2(&self) -> G2Affine {
         self.env().crypto().bls12_381().map_fp2_to_g2(self)
     }