feat: approval screens for the new Etna tx types

[meeh0w]

Description

• CP-9103
• Builds on top of feat: P-chain dynamic fees #74

Related PRs:

• https://github.com/ava-labs/extension-avalanche-playground/pull/53
• feat: add necessary APIs to facilitate DisableL1ValidatorTx signing avalanchejs#921
• https://github.com/ava-labs/avalanche-sdks/pull/692

Changes

• Adds approval screens for new Etna transactions

Testing

• With the playground app PR listed above. If AvalancheJS PR is not merged yet, you'll need to link it locally.
  • The code in the playground includes comments on how to obtain the required parameters
  • New transactions are: ConvertSubnetToL1, RegisterL1Validator, SetL1ValidatorWeight, IncreaseL1ValidatorBalance, DisableL1Validator, but ideally we should test everything.
  • According to the AvaCloud team, we don't need to support multi-sig on the new transactions just yet -- this part is not tested by me.

Checklist for the author

• I've covered new/modified business logic with Jest test cases.
• I've tested the changes myself before sending it to code review and QA.