Add back_off scheduler

[saulshanabrook]

Adds supports for the back off scheduler from experimental, and builds out mechanism in general to run custom schedulers.

[saulshanabrook]

@actions-user changelog

[Copilot]

Pull Request Overview

This PR adds support for the back_off scheduler from experimental, and builds out a general mechanism to run custom schedulers. The change enables users to create custom backoff schedulers with configurable parameters and use them in their egglog schedules.

• Adds BackOff class and back_off() function for creating backoff schedulers
• Updates run() function to accept an optional scheduler parameter
• Implements automatic scheduler hoisting and scoping mechanisms

Reviewed Changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
python/egglog/declarations.py	Adds BackOffDecl, LetSchedulerDecl types and updates RunDecl to support schedulers
python/egglog/egraph.py	Adds BackOff class, back_off() function, and updates run() to accept scheduler parameter
python/egglog/egraph_state.py	Implements scheduler processing logic and conversion to egg commands
python/egglog/pretty.py	Updates pretty printing to handle new scheduler declarations
python/tests/test_high_level.py	Adds comprehensive test cases for scheduler functionality
python/tests/test_pretty.py	Adds test cases for scheduler pretty printing
docs/reference/egglog-translation.md	Documents the new scheduler feature with examples
python/egglog/examples/jointree.py	Removes trailing empty lines

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #350 will not alter performance

_{Comparing schedule (a364098) with main (c7ba30d)}

Summary

✅ 7 untouched benchmarks