`generative` does return the last prompt from `MelleaSession.last_prompt()`

[avinash2692]

Description

Calling m.last_prompt() after running a genslot function does not return the last prompt.

Steps to Reproduce

import mellea
from mellea import LinearContext, generative

m = mellea.start_session(ctx=LinearContext())

@generative
def name_the_integer(x: int) -> str:
    """Generate the name of the integer in english and spanish"""

name_the_integer(m, x=5)

print(m.last_prompt())

Expected Behavior

Expected to print the last prompt.

Actual Behavior

prints nothing.

Additional Context

This is most likely due to the fact that we are not passing anything to generate_logs here:

mellea/mellea/stdlib/session.py

Lines 359 to 365 in 7ff924a

	result: ModelOutputThunk = self.backend.generate_from_context(
	action=gen_slot,
	ctx=self.ctx,
	model_options=model_options,
	format=format,
	tool_calls=tool_calls,
	)

We might want to set the generate_logs to a list here:

mellea/mellea/backends/__init__.py

Line 44 in 7ff924a

generate_logs: list[GenerateLog] | None = None,