Extend EC2 and EBS rule coverage

[dannysteenman]

What

Four rules extending the existing ec2 and ebs modules: unused Capacity Reservations, burstable-instance surplus credit charges, Auto Scaling groups with a fixed min=max range, and EBS Fast Snapshot Restore.

Why

These are waste patterns the current 22 EC2/EBS rules don't reach:

• On-Demand Capacity Reservations bill whether matched or not — an unmatched ODCR is pure waste at full on-demand rates.
• A t3/t4g instance persistently accruing CPUSurplusCreditsCharged is silently billing on-demand CPU on top of its instance rate — wrong family choice.
• An ASG with min == max pays for autoscaling architecture and gets none (direct analog of CLDBRN-AWS-DYNAMODB-4).
• Fast Snapshot Restore costs ~$0.75/hr per snapshot per AZ (~$540/mo for one snapshot in one AZ) and is frequently enabled once and forgotten.

Details

1. Capacity Reservation with unused capacity (available > 0, low utilization) over the lookback window — discovery, ec2 module.
2. Burstable instance with nonzero CPUSurplusCreditsCharged over the lookback window — discovery, ec2 module; reuses the CloudWatch dataset pattern of EC2-5.
3. ASG MinSize == MaxSize — IaC + discovery; research question: ASG belongs to the Auto Scaling service, so decide between extending ec2/ or opening an autoscaling/ module before assigning IDs.
4. Fast Snapshot Restore enabled — IaC (Terraform aws_ebs_fast_snapshot_restore) + discovery; extends ebs/ as CLDBRN-AWS-EBS-10.

• Per repo policy, static rules covered against both Terraform and CloudFormation inputs.