fix(backend/copilot): use shared get_openai_client() for transcript compaction

Replace per-call AsyncOpenAI instantiation with the process-cached
get_openai_client() from backend.util.clients, consistent with
optimize_blocks.py usage.

autogpt_platform/backend/backend/copilot/sdk/transcript.py

@@ -21,10 +21,8 @@ from dataclasses import dataclass
 from pathlib import Path
 from uuid import uuid4
 
-import openai
-
-from backend.copilot.config import ChatConfig
 from backend.util import json
+from backend.util.clients import get_openai_client
 from backend.util.prompt import CompressResult, compress_context
 
 logger = logging.getLogger(__name__)
@@ -705,20 +703,21 @@ def _messages_to_transcript(messages: list[dict]) -> str:
 async def _run_compression(
     messages: list[dict],
     model: str,
-    cfg: ChatConfig,
     log_prefix: str,
 ) -> CompressResult:
     """Run LLM-based compression with truncation fallback.
 
-    If the LLM call fails (API error, timeout, network), falls back to
+    Uses the shared OpenAI client from ``get_openai_client()``.
+    If no client is configured or the LLM call fails, falls back to
     truncation-based compression which drops older messages without
     summarization.
     """
+    client = get_openai_client()
+    if client is None:
+        logger.warning("%s No OpenAI client configured, using truncation", log_prefix)
+        return await compress_context(messages=messages, model=model, client=None)
     try:
-        async with openai.AsyncOpenAI(
-            api_key=cfg.api_key, base_url=cfg.base_url, timeout=30.0
-        ) as client:
-            return await compress_context(messages=messages, model=model, client=client)
+        return await compress_context(messages=messages, model=model, client=client)
     except Exception as e:
         logger.warning("%s LLM compaction failed, using truncation: %s", log_prefix, e)
         return await compress_context(messages=messages, model=model, client=None)
@@ -735,13 +734,15 @@ async def compact_transcript(
 
     Returns the compacted JSONL string, or ``None`` on failure.
     """
+    from backend.copilot.config import ChatConfig
+
     cfg = ChatConfig()
     messages = _transcript_to_messages(content)
     if len(messages) < 2:
         logger.warning("%s Too few messages to compact (%d)", log_prefix, len(messages))
         return None
     try:
-        result = await _run_compression(messages, cfg.model, cfg, log_prefix)
+        result = await _run_compression(messages, cfg.model, log_prefix)
         if not result.was_compacted:
             # Compressor says it's within budget, but the SDK rejected it.
             # Return None so the caller falls through to DB fallback.