Reorganize core into subpackages, add local KB, ruff/pyright tooling

- Split backend/app/core into weather/, discord/, memory_kb/, search/
  subpackages by responsibility, keeping config.py and llm.py as the
  shared foundation; updated all import sites accordingly.
- Add local Markdown knowledge base support (local_knowledge.py,
  knowledge_base/fgo.md, LOCAL_KB_* settings) that embeds and injects
  relevant docs into the system prompt by topic similarity.
- Add ruff and pyright as backend dev dependencies with basic config
  in pyproject.toml for linting and type checking.
- Document local machine quirks in CLAUDE.md (Postgres on port 8080,
  SSLKEYLOGFILE breaking litellm/pyright via OPENSSL_Uplink crashes).
- Add backend/run_dev.ps1 dev launcher and docs/discord-bot.md.

backend/app/api/chat.py

@@ -8,13 +8,13 @@ from sqlalchemy.orm import Session as DBSession
 
 from app.db.database import get_db
 from app.db.models import Session, Message
-from app.core import memory as mem
+from app.core.memory_kb import memory as mem
 from app.core import llm
-from app.core import knowledge
-from app.core.websearch import WEB_SEARCH_TOOL
+from app.core.memory_kb import knowledge
+from app.core.search.websearch import WEB_SEARCH_TOOL
 from app.core.config import DEFAULT_MODEL
-from app.core.tagging import tag_message_by_id
-from app.core.word_memory import record_message
+from app.core.memory_kb.tagging import tag_message_by_id
+from app.core.memory_kb.word_memory import record_message
 
 router = APIRouter(prefix="/chat", tags=["chat"])
 
@@ -102,7 +102,7 @@ async def stream_chat(req: ChatRequest, db: DBSession = Depends(get_db)):
     record_message(req.message)
     asyncio.create_task(tag_message_by_id(user_msg.id))
 
-    context = mem.get_context_messages(db, session.id)
+    context = await mem.get_context_messages(db, session.id)
 
     async def generate():
         import json as _json