Added proper agents config for mcp servers and skills.

Added the menu category delete route.
Fix: Show blank vouchers in tables
Fix: In rare cases, the old settements can stick around. fixed it.

.agents/skills/sqlalchemy-async/SKILL.md

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+---
+name: sqlalchemy-async
+description: Writes SQLAlchemy 2.0 async database queries using Psycopg3. Use whenever interacting with the PostgreSQL database.
+---
+# SQLAlchemy 2.0 Async Standards
+
+## Model Definitions
+- ALWAYS use SQLAlchemy 2.0 Declarative Base with `Mapped` and `mapped_column`.
+- Example: `id: Mapped[int] = mapped_column(primary_key=True)`
+- NEVER use the old `Column(Integer, primary_key=True)` syntax.
+
+## Querying
+- NEVER use `session.query()`. This is legacy 1.x syntax.
+- ALWAYS use `sqlalchemy.select()` combined with `await session.execute(stmt)`.
+- Extract results using `.scalars().all()` or `.scalar_one_or_none()`.
+
+## Session Management
+- Use `sqlalchemy.ext.asyncio.AsyncSession`.
+- Ensure all database I/O is awaited.