V3 transaction policy for anti-pinning

For instance, version 3 (v3) transactions could be capped at 200 virtual bytes (vB), as recommended by Peter Todd in his suggestion. Subsequent versions would see an incremental increase in size limits, with version 4 (v4) transactions allowing up to 400 vB, and version 5 (v5) up to 600 vB. This pattern would continue, reaching a potential maximum of 1600 vB in version 10 (v10) transactions, which corresponds to the largest historical size observed in Lightning Network's commitment transactions, as noted by @sdaftuar's observation.

This tiered approach allows each use case to select the appropriate transaction version based on their specific needs, providing flexibility and potentially optimizing network usage. The proposal acknowledges the variation in transaction requirements and recognizes the advantage of permitting users to choose a transaction version that best aligns with their desired descendant size.