[chore]sdk-examples: fix broken py-stellar-base imports (#2545)

* chore(sdk-examples): fix broken py-stellar-base imports

Standing-correctness audit against py-stellar-base 14.1.1:

learn/migrate/evm/smart-contract-deployment.mdx imported from the
pre-v9 `stellar_sdk.soroban.*` sub-package, which no longer exists
(the module layout is flat: `soroban_server`, `soroban_rpc`).
`SorobanServer` is re-exported at the top level, so the import is now
`from stellar_sdk import SorobanServer`. The second import
(`TransactionStatus` from `stellar_sdk.soroban.soroban_rpc`) referenced
a symbol that no longer exists under that name and was unused in the
snippet, so it was removed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* Update docs/learn/migrate/evm/smart-contract-deployment.mdx

Co-authored-by: Leigh <351529+leighmcculloch@users.noreply.github.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Co-authored-by: Leigh <351529+leighmcculloch@users.noreply.github.com>

Author: 3 people

docs/learn/migrate/evm/smart-contract-deployment.mdx

@@ -99,8 +99,7 @@ import time
 
 from stellar_sdk import Network, Keypair, TransactionBuilder
 from stellar_sdk import xdr as stellar_xdr
-from stellar_sdk.soroban import SorobanServer
-from stellar_sdk.soroban.soroban_rpc import TransactionStatus
+from stellar_sdk import SorobanServer
 
 # TODO: You need to replace the following parameters according to the actual situation
 secret = "SAAPYAPTTRZMCUZFPG3G66V4ZMHTK4TWA6NS7U4F7Z3IMUD52EK4DDEV"
@@ -120,7 +119,7 @@ source = soroban_server.load_account(kp.public_key)
 tx = (
     TransactionBuilder(source, network_passphrase)
     .set_timeout(300)
-    .append_install_contract_code_op(
+    .append_upload_contract_wasm_op(
         contract=contract_file_path,  # the path to the contract, or binary data
         source=kp.public_key,
     )