CSM: stakeShareLimit and keyRemovalCharge parameters adjustment

This proposal addresses the incremental tuning required to keep CSM a viable engine of Ethereum decentralization, raising the stakeShareLimit removes the growth ceiling for some 50 queued operators, while trimming the keyRemovalCharge re‑aligns safety costs with current gas levels. The change is prudent rather than drastic, unlocking broader community staking today and paving the way for future upgrades such as refinements to the bonding mechanism.