Fix minimizer producing programs with different sequences

[Copilot]

The minimizer's check() function incorrectly returned OK when sequences differed, allowing removal of required operations. This caused programs to produce different outputs after minimization (e.g., 2,2,2,2,9,9,... → 2,2,9,9,103,103,...).

Changes

src/eval/evaluator.cpp

• Reset incremental and virtual evaluators in clearCaches(), not just interpreter cache

src/eval/minimizer.cpp

• Add validation in minimize() to verify minimized program matches target sequence
• Add validation in optimizeAndMinimize() to verify final result matches original, reverting on mismatch

Example

// Before: only interpreter cache cleared
void Evaluator::clearCaches() { 
  interpreter.clearCaches(); 
}

// After: all evaluator state cleared
void Evaluator::clearCaches() {
  interpreter.clearCaches();
  inc_evaluator.reset();
  vir_evaluator.reset();
}

These defensive checks prevent incorrect minimization while the root cause in evaluator.check() remains under investigation.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Program evaluated to different sequence after minimization</issue_title> <issue_description>The random minimizer test failed with the following error:

2025-11-15 18:00:56|ERROR|Program evaluated to different sequence after minimization
before: 2,2,2,2,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9
min $0,4
mul $0,$0
clr $1,1
clr $1,$0
nrt $0,4
bor $0,1
fac $0,1
clr $2,1
mov $26,$0
equ $26,0
add $0,$26
dif $2,$0
mov $26,$0
equ $26,0
add $0,$26
dif $2,$0
ban $2,2
max $0,0
seq $0,12866
equ $2,$2
bin $0,$2
max $0,0
seq $0,135668

after: 2,2,9,9,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103,103
min $0,4
bor $0,1
seq $0,12866
seq $0,135668

libc++abi: terminating due to uncaught exception of type std::runtime_error: Program evaluated to different sequence after minimization

This could be a bug in the optimizer or the minimizer. Please fix it. </issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes loda-lang/loda-cpp#594

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