adding more tests

[harsh-ps-2003]

This PR :
Moved from static test directories to dynamic temp directories
Updated Committee implementation with test helpers
Improved test utilities and fixtures

and adds following tests :

• Header Tests :
  Tests initialization, quorum waiting, sync status handling, and digest buffer operations
  Includes edge cases like empty digests and timeout scenarios
  Added tests for multiple rounds and invalid vote handling

  test_header_builder_initialization() - Tests proper setup of HeaderBuilder
  test_wait_for_quorum() - Tests quorum collection mechanism
  test_header_builder_sync_status() - Tests sync state handling
  test_header_builder_with_empty_digests() - Edge case: empty digest handling
  test_header_builder_multiple_rounds() - Tests multi-round header building
  test_header_builder_quorum_timeout() - Tests timeout handling
  test_header_builder_invalid_votes() - Tests invalid vote rejection
  test_header_builder_digest_buffer() - Tests digest buffer operations

• Primary Synchronizer Tests :
  Tests concurrent request handling, retry logic on failures, partial response handling, invalid response data scenarios

  test_synchronizer_concurrent_requests() - Tests parallel request handling
  test_synchronizer_retry_on_failure() - Tests retry mechanism
  test_synchronizer_multiple_peers() - Tests multi-peer interactions
  test_synchronizer_invalid_response_data() - Tests invalid response handling

• Fetcher Tests :
  Tests basic fetching operations, timeout handling, error responses
  Covers multiple peer scenarios and response validation
  Tests retry mechanisms on failed fetches

  test_fetcher_basic() - Tests basic fetch operations
  test_fetcher_empty()
  test_fetcher_timeout() - Tests timeout handling
  test_fetcher_error_response() - Tests error response handling
  test_fetcher_multiple_peers() - Tests fetching from multiple peers
  test_fetcher_single_request() - Tests single request flow

• DAG tests :
  Tests basic DAG creation and operations, parent-child relationships, invalid parent scenarios, layer operations, complex hierarchies with multiple parents, cyclic insertion prevention

  test_dag_creation_and_basic_ops() - Tests basic DAG operations
  test_dag_parent_child_relationships() - Tests relationship validations
  test_dag_invalid_parent() - Tests invalid parent handling
  test_dag_layer_operations() - Tests layer-based operations
  test_dag_multiple_parents() - Tests multiple parent scenarios
  test_dag_cyclic_insertion_prevention() - Tests cycle prevention
  test_dag_complex_hierarchy() - Tests complex DAG structures

The cargo test passes :

running 48 tests
test primary::tests::header_tests::test_header_builder_digest_buffer ... ok
test primary::tests::header_tests::test_header_builder_initialization ... ok
test db::test::test_db ... ok
test primary::header_elector::test::test_first_round_valid_header_digests_stored ... ok
test primary::digests_receiver::tests::test_single_digest_received ... ok
test primary::digests_receiver::tests::test_multiple_under_capacity_digests_received ... ok
test primary::tests::header_tests::test_wait_for_quorum ... ok
test primary::tests::header_tests::test_header_builder_invalid_votes ... ok
test primary::digests_receiver::tests::test_multiple_over_capacity_digests_received ... ok
test synchronizer::feeder::test::feeder_failed_recovery ... ok
test synchronizer::tests::fetcher_tests::test_fetcher_basic ... ok
test synchronizer::tests::fetcher_tests::test_fetcher_empty ... ok
test synchronizer::feeder::test::feeder_full_recovery ... ok
test synchronizer::feeder::test::feeder_partial_recovery ... ok
test primary::digests_receiver::tests::test_multiple_very_over_capacity_digests_received ... ok
test synchronizer::tests::fetcher_tests::test_fetcher_timeout ... ok
test primary::tests::header_tests::test_header_builder_sync_status ... ok
test primary::tests::header_tests::test_header_builder_quorum_timeout ... ok
test primary::tests::header_tests::test_header_builder_with_empty_digests ... ok
test synchronizer::tests::fetcher_tests::test_fetcher_error_response ... ok
test types::dag::test::test_one_child_one_parent_check ... ok
test types::tests::dag_tests::test_dag_complex_hierarchy ... ok
test types::tests::dag_tests::test_dag_creation_and_basic_ops ... ok
test types::tests::dag_tests::test_dag_cyclic_insertion_prevention ... ok
test types::tests::dag_tests::test_dag_invalid_parent ... ok
test types::tests::dag_tests::test_dag_layer_operations ... ok
test types::tests::dag_tests::test_dag_multiple_parents ... ok
test types::tests::dag_tests::test_dag_parent_child_relationships ... ok
test worker::batch_maker::test::test_batch_maker_mixed_triggers ... ok
test worker::batch_maker::test::test_batch_maker_no_txs ... ok
test worker::batch_maker::test::test_batch_maker_rapid_transactions ... ok
test worker::batch_maker::test::test_batch_maker_size_trigger ... ok
test worker::batch_maker::test::test_batch_maker_timeout_trigger ... ok
test synchronizer::tests::fetcher_tests::test_fetcher_multiple_peers ... ok
test synchronizer::tests::fetcher_tests::test_fetcher_single_request ... ok
test synchronizer::tests::synchronizer_tests::test_synchronizer_concurrent_requests ... ok
test worker::batch_receiver::test::test_cancelled ... ok
test worker::quorum_waiter::test::test_cancelled ... ok
test worker::batch_receiver::test::test_single_batch_acknowledgement ... ok
test worker::quorum_waiter::test::test_batch_forgotten_after_quorum_received ... ok
test worker::quorum_waiter::test::test_duplicates_acknowledgements ... ok
test worker::quorum_waiter::test::test_multiple_batches_multiple_quorum ... ok
test worker::quorum_waiter::test::test_quorum_received ... ok
test worker::quorum_waiter::test::test_multiple_batches_single_quorum ... ok
test synchronizer::tests::synchronizer_tests::test_synchronizer_multiple_peers ... ok
test synchronizer::tests::synchronizer_tests::test_synchronizer_retry_on_failure ... ok
test primary::tests::header_tests::test_header_builder_multiple_rounds ... ok
test synchronizer::tests::synchronizer_tests::test_synchronizer_invalid_response_data ... ok

test result: ok. 48 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.38s

[harsh-ps-2003]

@EvolveArt can you TAL?