Final verification pass: refresh value-type matrix header

All 156 value-type matrix cases are enabled and passing; the header comment still described BROKEN-disabling from before the Safety/Operators/Series fixes landed. Reword it to state the matrix is fully green. Verified with a fresh meson build: 747/747 ok, exit 0, three consecutive clean runs, no glibc heap errors, plus throwaway probes in /tmp covering 1000-iteration add/remove/insert cycles for boxed value types, >32-bit Dictionary/HashSet lookups, default ascending sorts, Series<int>.to_array roundtrip and PriorityQueue<int64?> pop order.

src/tests/Integration/ValueTypeMatrix.vala

@@ -4,8 +4,9 @@ using Invercargill.Operators;
 
 // Value-type test matrix: behaviour of non-reference types (bool, int, uint,
 // long, ulong, int64?, uint64?, float?, double?, char, uchar, enum) across the
-// data structures. Cases failing at the time of writing are disabled with a
-// // BROKEN: comment naming type, structure, operation and symptom.
+// data structures. All 156 cases are enabled and passing: the failures this
+// matrix originally documented (boxed typed-array storage in Safety.vala,
+// operator marshalling/comparison branches, Series.to_array) are fixed.
 
 public enum ValueTypeFruit { APPLE, BANANA, CHERRY }