fix: use urllib.parse.urlencode for Scribe WebSocket query string

Replace manual f-string query parameter concatenation with
urllib.parse.urlencode so that free-form values (e.g. keyterms
with spaces or special characters) are properly percent-encoded.

Closes #779

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: kraenhansen

src/elevenlabs/realtime/scribe.py

@@ -2,6 +2,7 @@
 import base64
 import subprocess
 import typing
+import urllib.parse
 from enum import Enum
 from typing import overload
 
@@ -371,26 +372,27 @@ def _build_websocket_url(
         base = self.base_url.replace("https://", "wss://").replace("http://", "ws://")
 
         # Build query parameters
-        params = [
-            f"model_id={model_id}",
-            f"audio_format={audio_format}",
-            f"commit_strategy={commit_strategy}"
+        params: list[tuple[str, str]] = [
+            ("model_id", model_id),
+            ("audio_format", audio_format),
+            ("commit_strategy", commit_strategy),
         ]
 
-        # Add optional VAD parameters
-        if vad_silence_threshold_secs is not None:
-            params.append(f"vad_silence_threshold_secs={vad_silence_threshold_secs}")
-        if vad_threshold is not None:
-            params.append(f"vad_threshold={vad_threshold}")
-        if min_speech_duration_ms is not None:
-            params.append(f"min_speech_duration_ms={min_speech_duration_ms}")
-        if min_silence_duration_ms is not None:
-            params.append(f"min_silence_duration_ms={min_silence_duration_ms}")
-        if language_code is not None:
-            params.append(f"language_code={language_code}")
+        # Add optional parameters
+        optional: list[tuple[str, typing.Any]] = [
+            ("vad_silence_threshold_secs", vad_silence_threshold_secs),
+            ("vad_threshold", vad_threshold),
+            ("min_speech_duration_ms", min_speech_duration_ms),
+            ("min_silence_duration_ms", min_silence_duration_ms),
+            ("language_code", language_code),
+        ]
+        for key, value in optional:
+            if value is not None:
+                params.append((key, str(value)))
+
         if include_timestamps is not None:
-            params.append(f"include_timestamps={str(include_timestamps).lower()}")
+            params.append(("include_timestamps", str(include_timestamps).lower()))
 
-        query_string = "&".join(params)
+        query_string = urllib.parse.urlencode(params)
         return f"{base}/v1/speech-to-text/realtime?{query_string}"