ffi(nostr-sdk): add ClientSigner::PrivateKeys due to kotlin limitation

Author: yukibtc

bindings/nostr-sdk-ffi/src/client/signer/mod.rs

@@ -13,13 +13,25 @@ pub mod nip46;
 
 #[derive(Enum)]
 pub enum ClientSigner {
-    Keys { signer: Arc<Keys> },
-    NIP46 { signer: Arc<nip46::Nip46Signer> },
+    #[cfg(target_os = "android")]
+    PrivateKeys {
+        signer: Arc<Keys>,
+    },
+    #[cfg(not(target_os = "android"))]
+    Keys {
+        signer: Arc<Keys>,
+    },
+    NIP46 {
+        signer: Arc<nip46::Nip46Signer>,
+    },
 }
 
 impl From<ClientSigner> for signer::ClientSigner {
     fn from(value: ClientSigner) -> Self {
         match value {
+            #[cfg(target_os = "android")]
+            ClientSigner::PrivateKeys { signer } => Self::Keys(signer.as_ref().deref().clone()),
+            #[cfg(not(target_os = "android"))]
             ClientSigner::Keys { signer } => Self::Keys(signer.as_ref().deref().clone()),
             ClientSigner::NIP46 { signer } => Self::NIP46(signer.as_ref().deref().clone()),
         }
@@ -29,6 +41,11 @@ impl From<ClientSigner> for signer::ClientSigner {
 impl From<signer::ClientSigner> for ClientSigner {
     fn from(value: signer::ClientSigner) -> Self {
         match value {
+            #[cfg(target_os = "android")]
+            signer::ClientSigner::Keys(keys) => Self::PrivateKeys {
+                signer: Arc::new(keys.into()),
+            },
+            #[cfg(not(target_os = "android"))]
             signer::ClientSigner::Keys(keys) => Self::Keys {
                 signer: Arc::new(keys.into()),
             },