Add adaptive horizon criterion for residual

[geoffrey4444]

Proposed changes

Adds a criterion for adaptive horizon finding that adjusts resolution based on the residual of the most recent horizon find.

Depends on #6689 .

Note: I used the Cursor AI editor when preparing this PR, including tab completions and (for developing the first draft of the unit tests) agent mode. I reviewed all suggested code changes for correctness, and to the best of my knowledge, none of the code in this PR is from another codebase or violates any copyright or license.

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• The code is documented and the documentation renders correctly. Run
  make doc to generate the documentation locally into BUILD_DIR/docs/html.
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• The code follows the stylistic and code quality guidelines listed in the
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• The PR lists upgrade instructions and is labeled bugfix or
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Further comments

[geoffrey4444]

Neither test failure appears relevant to this PR

[knelli2]

You can squash everything together

[knelli2]

Sorry, one final thing. Can be squashed