Add Pillow for ImageField support

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: jsb2092

questionbank/requirements.txt

@@ -20,6 +20,7 @@ jiter==0.12.0
 Markdown==3.9
 openai==2.9.0
 packaging==25.0
+Pillow==11.0.0
 psycopg2-binary==2.9.11
 pydantic==2.12.5
 pydantic_core==2.41.5