The goal-based extractor passed raw fetched webpage content straight
into the LLM prompt via string substitution, bypassing the
prompt-injection hardening layer in src/prompt_security.py.
Split EXTRACTOR_PROMPT into EXTRACTOR_SYSTEM (task instructions +
goal, trusted) and a second message built with untrusted_context_message()
(raw page content, sandboxed with <<<UNTRUSTED_SOURCE_DATA>>> guards).
This aligns the extractor with every other external-content injection
site in the codebase (agent_loop, chat_processor, chat_routes).
Fixes#3044
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Giuseppe