* Initial plan
* Refactor theory_char::get_char_value to use std::optional
- Updated function signature to return std::optional<unsigned>
- Added const qualifier to function
- Updated both call sites to use modern C++17 patterns
- Used std::as_const to disambiguate overload resolution
Co-authored-by: NikolajBjorner <3085284+NikolajBjorner@users.noreply.github.com>
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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: NikolajBjorner <3085284+NikolajBjorner@users.noreply.github.com>
Issue #7502 shows that running nlsat eagerly during final check can block quantifier instantiation.
To give space for quantifier instances we introduce two levels for final check such that nlsat is only applied in the second and final level.
