Emit SMT object properties in deterministic order

[tautschnig]

The incremental SMT2 decision procedure emitted size_of_object and is_dynamic_object definitions by directly iterating the object map, which is an unordered map keyed by the objects' base expressions. The emission order therefore depended on expression hash values, which vary across platforms and configurations. For example, whether plain char is signed or unsigned changes the hashes of char-typed base expressions, reordering the emitted assertions and thereby producing textually different SMT problems for semantically identical inputs. Such differences needlessly perturb solver heuristics and defeat byte-for-byte comparison of generated formulas across platforms (a milder relative of the cross-platform instability discussed in #8991).

Sort the objects by their unique identifier before emitting their property definitions, so that the solver receives them in a stable order independent of hash values. The unit test that previously had to compare the sent commands as an unordered collection now requires the exact deterministic sequence.

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[Copilot]

Pull request overview

This PR makes the SMT2 incremental decision procedure emit object property definitions (size_of_object and is_dynamic_object) in a deterministic order by sorting tracked objects by their unique_id, avoiding cross-platform instability caused by unordered_map iteration order.

Changes:

• Sort object_map entries by object unique_id before emitting property definitions to the solver.
• Update the unit test to require the exact, deterministic sequence of emitted SMT commands (instead of unordered membership).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/solvers/smt2_incremental/smt2_incremental_decision_procedure.cpp	Sorts tracked objects by unique_id before emitting size_of_object / is_dynamic_object definitions to ensure deterministic SMT output.
unit/solvers/smt2_incremental/smt2_incremental_decision_procedure.cpp	Updates expectations to assert the precise command emission order now guaranteed by the implementation.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.77%. Comparing base (f5bf9cc) to head (bf92304).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #9119      +/-   ##
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- Coverage    80.77%   80.77%   -0.01%     
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  Files         1712     1712              
  Lines       189814   189820       +6     
  Branches        73       73              
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+ Hits        153328   153331       +3     
- Misses       36486    36489       +3     

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