Update docs to clarify other client HKDF support (#1796)

Author: 1egoman

.changeset/slow-dingos-look.md

@@ -0,0 +1,5 @@
+---
+'livekit-client': patch
+---
+
+Update docs to clarify other client HKDF support

src/e2ee/KeyProvider.ts

@@ -91,8 +91,10 @@ export class ExternalE2EEKeyProvider extends BaseKeyProvider {
 
   /**
    * Accepts a passphrase that's used to create the crypto keys.
-   * When passing in a string, PBKDF2 is used.
-   * When passing in an Array buffer of cryptographically random numbers, HKDF is being used. (recommended)
+   * When passing in a string, PBKDF2 is used. (recommended for maximum compatibility across SDKs)
+   * When passing in an ArrayBuffer of cryptographically random numbers, HKDF is used.
+   *
+   * Note: Not all client SDKS support HKDF.
    * @param key
    */
   async setKey(key: string | ArrayBuffer) {