MaxCode: Integrate MergeAgent into PrimaryAgent pipeline and update conversion tools

[gvanica]

Summary

Updates the core pipeline orchestration so that directory-mode conversions now use MergeAgent to merge and filter repository files before converting, instead of processing each file independently. Also updates the migration tool to handle the new output format and auto-run verification.

Key changes

primary_agent.py (+632 / -221 lines) — Major rewrite

• Directory path: Now calls MergeAgent.run() to produce a single merged model file + optional utils file, then converts the merged output in one shot. Previously processed each file independently, leading to inconsistent cross-file references.
• Single-file path: Unchanged — still converts individual files directly.
• Debug loop: Integrated iterative debug loop with syntax checking and AST validation of converted output.
• Imports new agents: maxtext_conversion_agent, validation_agent.

model_conversion_agent.py (+47 lines modified)

• Updated to accept merged multi-file input alongside single-file input.
• Passes RAG context through to conversion prompts.

single_file_agent.py (+62 lines modified)

• Tightened single-file conversion path with improved error handling.
• Better markdown stripping for LLM output.

repo_agent.py (2 lines)

• Minor fix to repository cloning logic.

migration_tool.py (+136 lines modified)

• Handles the new model + utils dual-output format from PrimaryAgent.
• Auto-runs verification scorecard after conversion completes.
• Improved output path handling.

Files

File	Change	Lines
agents/migration/primary_agent.py	Modified	+632 / -221
agents/migration/model_conversion_agent.py	Modified	+47
agents/migration/single_file_agent.py	Modified	+62
agents/migration/repo_agent.py	Modified	+2 / -2
tools/migration_tool.py	Modified	+136

Dependencies

This PR references MergeAgent, ValidationAgent, and MaxTextConversionAgent which are introduced in sibling PRs (#24, #25, #27). It also uses the updated prompts from #26.

Test plan

• Run PrimaryAgent.run() on a directory containing multiple model files — verify it merges before converting
• Run PrimaryAgent.run() on a single file — verify single-file path still works
• Verify convert_code tool returns model + utils output and prints verification scorecard
• Confirm debug loop catches syntax errors and retries

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Split from #17 — PR 5 of 8

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