Feat/query module

[saitunc]

Closes #204

This PR is intended to implement the query features mentioned in issue #204 as a module.

Changes

Core Implementation

• Added BlockExplorer interface defining waitTxInclusion() and getBlock() methods F(338ca4e)
• Implemented GraphqlBlockExplorer in @proto-kit/sdk for client-side remote queries
• Implemented InMemoryBlockExplorer in @proto-kit/sequencer for server-side local queries (Final form of those two are at 92fa991)

Features

• waitTxInclusion(): Poll transaction status until included in a block
  • Returns transaction state: INCLUDED, PENDING, or UNKNOWN
  • Configurable polling interval and attempt limits
• getBlock(): Retrieve block data by hash or height
  • Returns block model with transactions and metadata
  • Defined GraphQL fragment for efficient query composition (92fa991)

Tests

• Added comprehensive test cases for both explorer implementations
• Tests cover transaction inclusion polling and block retrieval