backend: replace LAST_FULL_PROMPT/LAST_CAT_INTERACTION with unified PROMPT_HISTORY deque

- globals.py: add collections.deque(maxlen=10) PROMPT_HISTORY with _prompt_id_counter
- globals.py: add legacy accessor functions _get_last_fallback_prompt() and _get_last_cat_interaction()
- bot.py: append to PROMPT_HISTORY instead of setting LAST_CAT_INTERACTION, remove 500-char truncation, add guild/channel/model fields
- image_handling.py: same pattern for Cat media responses
- llm.py: append fallback prompts to PROMPT_HISTORY with response filled after LLM reply
- routes/core.py: new GET /prompts and GET /prompts/{id} endpoints, legacy /prompt and /prompt/cat use accessor functions

bot/bot.py

@@ -360,15 +360,24 @@ async def on_message(message):
                         if globals.EVIL_MODE:
                             effective_mood = f"EVIL:{getattr(globals, 'EVIL_DM_MOOD', 'evil_neutral')}"
                         logger.info(f"🐱 Cat response for {author_name} (mood: {effective_mood})")
-                        # Track Cat interaction for Web UI Last Prompt view
+                        # Track Cat interaction in unified prompt history
                         import datetime
-                        globals.LAST_CAT_INTERACTION = {
+                        globals._prompt_id_counter += 1
+                        guild_name = message.guild.name if message.guild else "DM"
+                        channel_name = message.channel.name if message.guild else "DM"
+                        globals.PROMPT_HISTORY.append({
+                            "id": globals._prompt_id_counter,
+                            "source": "cat",
                             "full_prompt": cat_full_prompt,
-                            "response": response[:500] if response else "",
+                            "response": response if response else "",
                             "user": author_name,
                             "mood": effective_mood,
+                            "guild": guild_name,
+                            "channel": channel_name,
                             "timestamp": datetime.datetime.now().isoformat(),
-                        }
+                            "model": "Cat LLM",
+                            "response_type": response_type,
+                        })
                 except Exception as e:
                     logger.warning(f"🐱 Cat pipeline error, falling back to query_llama: {e}")
                     response = None