feat: add user alias mapping for jealousy detection context

Adds user_aliases config section mapping Discord IDs to known nicknames.
Aliases are anonymized and injected into LLM analysis context so it can
recognize when someone name-drops another member (even absent ones).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

utils/llm_client.py

@@ -489,6 +489,7 @@ class LLMClient:
         channel_context: str = "",
         user_notes_map: dict[str, str] | None = None,
         new_message_start: int | None = None,
+        user_aliases: str = "",
     ) -> dict | None:
         """Analyze a conversation block in one call, returning per-user findings."""
         if not messages:
@@ -497,6 +498,8 @@ class LLMClient:
         convo_block = self._format_conversation_block(messages, new_message_start=new_message_start)
 
         user_content = f"=== CONVERSATION BLOCK ===\n{convo_block}\n\n"
+        if user_aliases:
+            user_content += f"=== KNOWN MEMBER ALIASES (names other members use to refer to each other) ===\n{user_aliases}\n\n"
         if user_notes_map:
             notes_lines = [f"  {u}: {n}" for u, n in user_notes_map.items() if n]
             if notes_lines: