Some builtin tactics do not have their config types in `Init`

Prerequisites

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• Reduce the issue to a minimal, self-contained, reproducible test case.
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Description

The syntax of builtin elaborators such as solve_by_elim and apply_rules (did not find any other) are defined in Init, but their config types are not.
This leads to an elaboration failure for the config type in e.g., solve_by_elim -backtracking.

Context

Steps to Reproduce

example : True := by
  solve_by_elim -backtracking

Expected behavior: No elaboration failure; should prove the goal

Actual behavior: error evaluating configuration, environment does not yet contain type Lean.Meta.SolveByElim.SolveByElimConfig

Versions

"4.23.0-nightly-2025-07-10"

Additional Information

Impact

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Begin with the builtin elaborator definitions in Init for solve_by_elim and apply_rules, then inspect how their configuration types are resolved. Run the provided solve_by_elim -backtracking example as the initial reproduction. Done means the example elaborates without the missing SolveByElimConfig error and proves the goal.