docs: Rewrite Tutorial 04 Guardian steps for Guardian Intrinsics

[planetf1]

Context

GuardianCheck is deprecated since v0.4 (mellea/stdlib/components/guardian.py:106 emits DeprecationWarning: Use the Guardian Intrinsics instead). Tutorial 04 ("Making Agents Reliable") Steps 4–6 all use GuardianCheck, making them non-functional for new users.

Raised in PR #601 review:

• E1 — comment: Guardian output is confusing (deprecation warnings + "Guardian returned empty result" + false-positive safety failures)
• M4 — comment: ModuleNotFoundError: No module named 'llguidance' — this is a HuggingFace-backend-only dependency, not needed for Ollama

What needs to change

1. Replace all GuardianCheck usage in Steps 4–6 with the Guardian Intrinsics API
2. Update imports and example code
3. Verify the tutorial runs end-to-end with Ollama + granite4:micro
4. Remove or update references to llguidance (HF-only)
5. Capture and include representative sample output

Files

• docs/docs/tutorials/04-making-agents-reliable.md (primary)

Acceptance criteria

• Tutorial 04 runs without deprecation warnings
• No references to GuardianCheck
• Sample output included for each step