Add lint and build commands to AGENTS.md for agent context

The amp agent sometimes runs hlint directly instead of using the project's lint command. AGENTS.md is injected into agent context but doesn't include the actual commands to use.

Problem

On longer threads, the agent may forget or not know that:

• Use lint <file> not hlint
• Use bild <namespace> to build
• Use typecheck.sh <file> for type checking

These are documented in Omni/Ide/README.md but that file is NOT injected into context.

Fix

Add a "Common Commands" section to AGENTS.md:

## Common Commands

**Build:**

bild Omni/Jr.hs # Build a Haskell namespace bild Biz/Cloud/Api.py # Build a Python namespace

**Lint and Format:**

lint Omni/Cli.hs # Lint a file (DO NOT use hlint directly) lint --fix **/*.py # Lint and auto-fix Python files

**Type Check:**

typecheck.sh Omni/Bild/Example.py # Run mypy on Python files

**Test:**

bild --test Omni/Jr.hs # Build and run tests for a namespace

**Run:**

Omni/Ide/run.sh Omni/Jr.hs # Build (if needed) and run

Place this section after "Directory Structure" and before "Documentation".

Files: AGENTS.md