Bake reflection into the experiment loop

[alexbenari]

Summary

This updates program.md to add a lightweight reflection step before and after each experiment.

The workflow now asks the agent to:

• initialize a musings.md file during setup
• write down a short rationale for the proposed idea, including the underlying intuition and any relevant ML grounding, before changing train.py
• record a brief post-mortem after the run, capturing whether the attempt succeeded and what was learned.

The resulting musings.md leaves behind a useful learning trail for humans (at least this human) interested in the nuances of ML theory and their application.
It may also improve the agent's idea generation quality by making the loop more systematic, though that would need more deliberate validation.

Changes

• add musings.md initialization to the experiment setup checklist
• require a short pre-execution writeup for each proposed idea
• require a short post-run reflection on whether the attempt worked and what was learned

Testing

• docs/process change only

[morozow]

@alexbenari A memorizable text file for the agent is a good idea. Do not forget to instruct the agent to read this file before starting. A prompt-engineered musings.md context provides more valuable sense for agent than a large amount of historical data alone.

I experimented with a historical file-based context approach in my fork of autoresearch repo, highlighted in discussion #234, and I agree that historical file-system context works well.

[alexbenari]

It might be useful for resuming agent work as you suggest, although for that purpose musings.md specifically seems somewhat of an overkill. A much smaller file would do (perhaps even the existing results.tsv).
I think the main value of musings.md is as 1. a learning aid for the human 2. steering the agent's reasoning

[morozow]

1. learning aid for the human – the only practical option here is a musings.md collection/DB, or similar store. Nobody is going to read every LLM experimental runtime outcome
2. steering the agent's reasoning – is essentially the same as "useful for resuming agent work as you suggest"

Nevertheless, memorizable text file for agent is still a good idea.