Several changes:

- Extend fixed-bit FI to both directions
- really randomized restart
- MSB for fixed-bits
- Forward propagation (band, lshift, rshift) with good justifications (strengthen during saturation)

src/test/polysat.cpp

@@ -1952,7 +1952,6 @@ static void STD_CALL polysat_on_ctrl_c(int) {
 
 void tst_polysat() {
     using namespace polysat;
-    test_polysat::test_ineq_axiom4(32, 7);
 #if 0  // Enable this block to run a single unit test with detailed output.
     collect_test_records = false;
     test_max_conflicts = 50;