instrument: fix AHD node-tracking/tie-break/live-latch defects and close staged-envelope-curve test gaps

src/core/wire/bytes.h

@@ -30,6 +30,11 @@ inline void putLE(std::vector<std::uint8_t>& out, T v) {
     }
 }
 
+// Signed 64-bit values ride the wire as their two's-complement unsigned image (the putLE
+// call site's u64 cast). The one home for that cast — component_state_io and params_payload
+// both need it and must not carry their own copies.
+inline std::uint64_t asU64(std::int64_t v) { return static_cast<std::uint64_t>(v); }
+
 // IEEE-754 double <-> u64 bit-cast for the wire (memcpy is the only defined
 // type-pun in C++17). Doubles ride the wire as their u64 bit image via putLE.
 inline std::uint64_t doubleToBits(double d) {