Introduce `TestPhaseManager` construct to tag tests' elements

[marioevz]

Introduce a generalized TestPhaseManager which would be similar to this:

execution-spec-tests/src/ethereum_test_specs/benchmark.py

Lines 45 to 95 in d5d23c2

	class BenchmarkManager:
	"""Context manager for managing benchmark test phases."""
	def __init__(self):
	"""Initialize the BenchmarkManager with empty transaction and block lists."""
	self.setup_transactions: List[Transaction] = []
	self.setup_blocks: List[Block] = []
	self.execution_transactions: List[Transaction] = []
	self.execution_blocks: List[Block] = []
	@contextmanager
	def setup(self):
	"""Context manager for the setup phase of a benchmark test."""
	token = _current_phase.set(BenchmarkPhase.SETUP)
	try:
	yield self
	finally:
	_current_phase.reset(token)
	@contextmanager
	def execution(self):
	"""Context manager for the execution phase of a benchmark test."""
	token = _current_phase.set(BenchmarkPhase.EXECUTION)
	try:
	yield self
	finally:
	_current_phase.reset(token)
	def add_transaction(self, tx: Transaction):
	"""Add a transaction to the current phase."""
	current_phase = _current_phase.get()
	if current_phase == BenchmarkPhase.SETUP:
	self.setup_transactions.append(tx)
	elif current_phase == BenchmarkPhase.EXECUTION:
	self.execution_transactions.append(tx)
	else:
	self.setup_transactions.append(tx)
	def add_block(self, block: Block):
	"""Add a block to the current phase."""
	current_phase = _current_phase.get()
	if current_phase == BenchmarkPhase.SETUP:
	self.setup_blocks.append(block)
	elif current_phase == BenchmarkPhase.EXECUTION:
	self.execution_blocks.append(block)
	else:
	self.setup_blocks.append(block)
	def get_current_phase(self) -> Optional[BenchmarkPhase]:
	"""Get the current benchmark phase."""
	return _current_phase.get()

But it has an instance defined at the ethereum_test_types level so it can be accessed by Transaction, Block and perhaps other classes to tag themselves as part of an explicit phase of a given test.

This would be particularly important in benchmark tests where we need some transactions and accounts to be part of a "setup" phase so execute can pick these up and treat them accordingly when running tests in BloatNet for example.

test_phase_manager = TestPhaseManager()

...

class Transaction(
    TransactionGeneric[HexNumber], TransactionTransitionToolConverter, SignableRLPSerializable
):
    """Generic object that can represent all Ethereum transaction types."""
    ...
    test_phase: str | None = Field(default_factory=lambda _: test_phase_manager.get())

We could then create a generic pytest fixture in ./src/pytest_plugins/shared/execute_fill.py that returns the test_phase_manager in every case.

[marioevz]

@fselmo @LouisTsai-Csie I hope I explained the idea correctly, and to be honest I'm not sure if it's even possible, but let's use this issue to discuss :)