Under STRESS_OPT_REPEAT/JitOptRepeat, a second optimization iteration could mis-evaluate a constant relop and steer control flow down the wrong branch, reaching an unreachable % 0 path. This change makes redundant-branch optimization type-correct when interpreting constant value numbers and adds a focused regression covering the reported repro shape.

• JIT fix (RBO constant-VN handling)

  • Updated src/coreclr/jit/redundantbranchopts.cpp to compare constant relop VNs against a zero VN of the actual VN type instead of hardcoding TYP_INT.
  • Applied the same correction in both constant-relop evaluation sites used by branch elimination/jump-threading.

• Regression coverage

  • Added src/tests/JIT/Regression/JitBlue/Runtime_129386/Runtime_129386.cs.
  • Added src/tests/JIT/Regression/JitBlue/Runtime_129386/Runtime_129386.csproj with JitEnableOptRepeat=1, JitOptRepeat=Fn30000002142, and JitOptRepeatCount=2.
  • Test asserts expected result/trace path and fails on the prior wrong-branch behavior (DivideByZeroException path).

// before
relopValue = (treeNormVN == vnStore->VNZeroForType(TYP_INT)) ? 0 : 1;

// after
relopValue = (treeNormVN == vnStore->VNZeroForType(vnStore->TypeOfVN(treeNormVN))) ? 0 : 1;