Issue 4: Generator's `confidence` field is captured but never used

[sanjaigridsandguides]

Problem

• GeneratedAnswer has a confidence: float field.
• generate_node prints the confidence but does not write it into state.
• The validator prompt refers to confidence, but no value is available there.

Impact

• Dead schema field that pretends to influence behaviour but doesn't.
• Misleads future maintainers into thinking confidence-gating is in place.

Required Fix

• Either propagate confidence through state and actually use it in the routing logic, or remove the field from the Pydantic schema and the prompt entirely.