test: Add Initial Unit Tests for BiniBFT Proposal and Request Parsing

[Ayush-AM]

Description

This PR introduces the initial set of unit tests for the BiniBFT proposal and request parsing logic on the binibft branch, fulfilling the requirements for Issue #16. No production behavior or implementation details have been modified.

Changes Included

• types_test.go: Added table-driven round-trip tests (serialization and deserialization) for Transaction, BlockData, BlockHeader, and Block. Handled standard and edge cases (e.g., empty fields).
• verifier_test.go: Implemented table-driven tests for VerifyProposal and RequestsFromProposal to ensure they accurately extract the expected RequestInfo lists from valid block payloads.
• request_inspector_test.go: Added table-driven tests for RequestID to verify the correct extraction of ClientID and ID from serialized transactions.

Related Issues

• Resolves Add Initial Unit Tests for BiniBFT Proposal and Request Parsing (binibft branch) #16
• Reference: BiniBFT - Testing, Integration, and Documentation LF-Decentralized-Trust-Mentorships/mentorship-program#79

Acceptance Criteria Met

• New tests added and pass locally with go test ./... on binibft.
• Tests are table-driven covering at least 2 cases per function group.
• No production behavior changes included (tests-only).
• Commits are signed off (-s) following standard Hyperledger contribution guidelines.