Generalize Binf → Box Constraints

[arnavk23]

Successfully implemented the generalization from Binf (L∞-ball) constraints to Box constraints across all applicable shifted proximal operators, following the pattern established in PR #104 for ShiftedRootNormLhalfBox.

Key Changes

1. Enhanced existing Box variants: ShiftedIndBallL0Box, ShiftedGroupNormL2Box, and ShiftedRootNormLhalfBox
   Dual signature support: Each Box variant now supports both:
   General box constraints: shifted(h, x, l, u) for arbitrary bounds [l, u]
   Symmetric constraints: shifted(h, x, Δ, χ) for symmetric bounds [-Δ, Δ] (backward compatibility)

2. Box implementations now override the corresponding Binf method signatures
   Legacy code using (Δ, χ) signatures automatically returns Box variants instead of Binf variants
   Maintains full backward compatibility while providing enhanced functionality

3. Enhanced getproperty method to provide backward-compatible access to ψ.Δ and ψ.χ properties on Box variants
   Automatic conversion from symmetric box constraints [-Δ, Δ] back to radius Δ when accessed
   Seamless integration with existing code expecting Binf-style properties

4. Updated all test references from ShiftedGroupNormL2Binf and ShiftedIndBallL0BInf to their respective Box variants
   Fixed type expectations to match Box variant signatures with additional type parameters
   Implemented appropriate numerical tolerance using isapprox with atol for precision differences between algorithms

5. Verified set_radius! methods work correctly with all Box variants
   Proper export statements and module includes already in place
   Smart bounds conversion: set_radius!(ψ, Δ) automatically sets bounds to [-Δ, Δ]

Closes #88

[arnavk23]

@dpo please review this pr.

[dpo]

Many thanks @arnavk23 ! I'll have a look. Please don't commit the Manifest.toml though.

[Copilot]

Pull Request Overview

This PR successfully generalizes shifted proximal operators from Binf (L∞-ball) constraints to Box constraints, enabling support for arbitrary box bounds [l, u] while maintaining backward compatibility with symmetric constraints [-Δ, Δ].

Key Changes

• Enhanced existing Box variants (ShiftedIndBallL0Box, ShiftedGroupNormL2Box) with dual signature support for both general and symmetric constraints
• Added backward compatibility layer that automatically returns Box variants for legacy Binf signatures
• Updated test references and type expectations to match the new Box variant signatures

Reviewed Changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 2 comments.

File	Description
test/runtests.jl	Updated test references from Binf to Box variants and adjusted type expectations with additional type parameters
src/shiftedIndBallL0Box.jl	New Box variant for IndBallL0 with general box constraints and backward compatibility
src/shiftedGroupNormL2Box.jl	New Box variant for GroupNormL2 with general box constraints and backward compatibility
src/ShiftedProximalOperators.jl	Added includes for new Box variants and enhanced getproperty method for backward compatibility

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[codecov]

Codecov Report

❌ Patch coverage is 72.34043% with 26 lines in your changes missing coverage. Please review.
✅ Project coverage is 72.54%. Comparing base (753a97f) to head (aa30ee7).
⚠️ Report is 15 commits behind head on master.

Files with missing lines	Patch %	Lines
src/shiftedIndBallL0Box.jl	57.57%	14 Missing ⚠️
src/shiftedGroupNormL2Box.jl	80.00%	9 Missing ⚠️
src/ShiftedProximalOperators.jl	81.25%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #144      +/-   ##
==========================================
- Coverage   73.71%   72.54%   -1.18%     
==========================================
  Files          22       26       +4     
  Lines         898     1060     +162     
==========================================
+ Hits          662      769     +107     
- Misses        236      291      +55     

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[Copilot]

Pull Request Overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

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[dpo]

@arnavk23 I think one of the warnings due to methods being overwritten is caused by this PR?! I'll open issues for the others.

[Copilot]

Pull Request Overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 4 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 7 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 12 out of 13 changed files in this pull request and generated 2 comments.

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