protocol params: governance/config strategy for changing limits safely

[TheNewAutonomy]

Goal

Define how protocol parameters are set and changed safely (cycle duration, limits, fees, etc.).

Scope

• Which params are compile-time vs config vs on-chain
• Safe bounds and validation
• Upgrade path for param changes
• Document defaults for dev/test/mainnet

Acceptance criteria

• Parameter schema documented and validated
• Nodes refuse unsafe/out-of-bounds params

[TheNewAutonomy]

Progress on parameter governance/safety:

• Enforced config validation on startup (NodeConfig::validate() is now called from catalyst-cli start).
• Added documentation of current parameter sources + safety rules in docs/protocol-params.md.

Remaining (suggested follow-ups for this ticket):

• Decide which params must be compile-time vs config vs on-chain (governance strategy).
• Extend NodeConfig::validate() with explicit safe bounds for any remaining tunables (fees/limits) once policy is decided.