* Fix: Validate and limit chat question input in ChatStreamingView
Add max_length=4000 to ChatStreamingSerializer.q and replace the bare
request.data["q"] read with proper serializer.is_valid(raise_exception=True)
so oversized or missing questions are rejected with HTTP 400 before
reaching the LLM.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
* Fix: Add defensive prompt framing to mark document content as untrusted
* Also adds a system prompt which is treated higher that this is untrusted stuff
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Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>