chore: bump openai-agents to 0.19.0 and openai to 2.48.0

openai-agents 0.19.0 includes MCP Python SDK v2 compatibility fixes
(see openai/openai-agents-python#<pr>). The previous openai==2.44.0
pin and its associated comment (InputTokensDetails issue #187) are
resolved in openai-agents 0.19.0.

Author: mixxer

pyproject.toml

@@ -38,12 +38,8 @@ dependencies = [
     "click==8.4.0",
     "watchdog==6.0.0",
     "litellm==1.87.2",
-    "openai-agents==0.17.3",
-    # openai 2.45.0 added a required `cache_write_tokens` field to
-    # InputTokensDetails that openai-agents 0.17.3 does not set, crashing
-    # usage parsing on every response (issue #187). Pin below 2.45 until
-    # openai-agents catches up.
-    "openai==2.44.0",
+    "openai-agents==0.19.0",
+    "openai==2.48.0",
     "pyyaml==6.0.3",
     "python-dotenv==1.2.2",
     "json-repair==0.59.10",