feat: add --fastsync-server-path flag to configure remote server binary path

tests/test_transport_ssh.c

@@ -9,14 +9,14 @@
 static void test_ssh_connect_invalid_dest() {
   /* Missing colon — parse_remote_dest should fail and return NULL */
   /* cppcheck-suppress constVariablePointer */
-  Client* client = client_connect_ssh("invalid-destination-no-colon", 22);
+  Client* client = client_connect_ssh("invalid-destination-no-colon", 22, NULL);
   EXPECT_NULL(client);
 }
 
 /* Test client_connect_ssh with empty destination */
 static void test_ssh_connect_empty_dest() {
   /* cppcheck-suppress constVariablePointer */
-  Client* client = client_connect_ssh("", 22);
+  Client* client = client_connect_ssh("", 22, NULL);
   EXPECT_NULL(client);
 }
 
@@ -24,7 +24,7 @@ static void test_ssh_connect_empty_dest() {
  * parse_remote_dest succeeds, ssh is exec'd and fails, but the function
  * creates a Client that must be cleaned up. */
 static void test_ssh_connect_malformed() {
-  Client* client = client_connect_ssh(":", 22);
+  Client* client = client_connect_ssh(":", 22, NULL);
   /* ssh binary exists, so exec succeeds; the function returns a Client.
    * We just verify it doesn't crash and clean up properly. */
   if (client != NULL) {
@@ -37,7 +37,7 @@ static void test_ssh_connect_malformed() {
 /* Test client_connect_ssh with valid format but unreachable host.
  * The function launches ssh which will fail to connect, returns a Client. */
 static void test_ssh_connect_unreachable() {
-  Client* client = client_connect_ssh("nonexistent.invalid:/remote/path", 22);
+  Client* client = client_connect_ssh("nonexistent.invalid:/remote/path", 22, NULL);
   if (client != NULL) {
     client_disconnect(client);
     client_delete(client);