Generalize image roast to handle selfies, memes, and any image

The prompt was scoreboard-only, so selfies got nonsensical stat-based
roasts. Now the LLM identifies what's in the image and roasts accordingly.

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

cogs/chat.py

@@ -11,7 +11,7 @@ from discord.ext import commands
 logger = logging.getLogger("bcs.chat")
 
 _PROMPTS_DIR = Path(__file__).resolve().parent.parent / "prompts"
-SCOREBOARD_ROAST = (_PROMPTS_DIR / "scoreboard_roast.txt").read_text(encoding="utf-8")
+IMAGE_ROAST = (_PROMPTS_DIR / "scoreboard_roast.txt").read_text(encoding="utf-8")
 
 _IMAGE_TYPES = {"png", "jpg", "jpeg", "gif", "webp"}
 
@@ -115,9 +115,9 @@ class ChatCog(commands.Cog):
             await typing_ctx.__aenter__()
 
         if image_attachment:
-            # --- Image path: scoreboard roast ---
+            # --- Image path: roast the image ---
             image_bytes = await image_attachment.read()
-            user_text = content if content else "Roast this scoreboard."
+            user_text = content if content else ""
             logger.info(
                 "Image roast request in #%s from %s (%s, %s)",
                 message.channel.name,
@@ -127,7 +127,7 @@ class ChatCog(commands.Cog):
             )
             response = await self.bot.llm_heavy.analyze_image(
                 image_bytes,
-                SCOREBOARD_ROAST,
+                IMAGE_ROAST,
                 user_text=user_text,
                 on_first_token=start_typing,
             )