fix(v1.0.2): Array grow from 0, Map/Set rehash, checked div/mod

- Array_Push grows from cap 0 (same min as Insert) to avoid segfault
- Map/StringMap/Set: default min cap 8 and auto-rehash at ~50% load
- Integer / and % emit bux_div_i64 / bux_mod_i64 (panic instead of SIGFPE)
- Bump version to 1.0.2; stdlib golden regressions; fmt clean

tests/stdlib_golden/array/src/Main.bux

@@ -11,6 +11,15 @@ import Std::Test::{
 };
 
 func Main() -> int {
+    // Zero-capacity grow (v1.0.2): must not segfault
+    var z: Array<int> = Array_New<int>(0);
+    Array_Push<int>(&z, 7);
+    Array_Push<int>(&z, 8);
+    Test_AssertEqInt(Array_Len<int>(&z) as int, 2);
+    Test_AssertEqInt(Array_Get<int>(&z, 0), 7);
+    Test_AssertEqInt(Array_Get<int>(&z, 1), 8);
+    Array_Free<int>(&z);
+
     var arr: Array<int> = Array_New<int>(2);
     Array_Reserve<int>(&arr, 8);
     Test_AssertTrue(Array_Cap<int>(&arr) >= 8);