[F49 step 1 + F56] callback router: peel envelope before parsing subscription / 0x11 frames

The router used to call NmxSubscriptionMessage::parse_inner directly
on the COM-stub-delivered body, but the wire bytes arrive wrapped in
a ProcessDataReceived envelope (46-byte header + optional 4-byte
length prefix); parse_inner expects post-envelope bytes. Result:
every 0x33 DataUpdate that ever arrived was silently dropped.

Mirrors the .NET reference's MxNativeSession.OnCallbackReceived flow
at cs:582-606 — three sequential parse attempts:
  1. NmxOperationStatusMessage::try_parse_process_data_received_body  (already wired)
  2. NmxReferenceRegistrationResultMessage::try_parse_...              (NEW — was missing)
  3. NmxSubscriptionMessage::try_parse_process_data_received_body      (NEW — was wrong)

Adds:
- NmxSubscriptionMessage::try_parse_process_data_received_body — peels
  envelope via NmxObservedEnvelope::parse_process_data_received_body_flexible,
  then dispatches to existing parse_inner.
- NmxReferenceRegistrationResultMessage::try_parse_process_data_received_body —
  same shape, for the 0x11 registration-result frame.
- Router branch for 0x11 — currently traces the assigned item_handle and
  drops the frame (matches the .NET reference, which fires a
  ReferenceRegistrationReceived event with no consumer in the codebase).
- Router fall-through trace! when neither path matches, so future
  unparseable bodies surface in RUST_LOG=trace instead of vanishing.
- DcomCallbackSink::forward — trace! per inbound callback so
  RUST_LOG=mxaccess_callback=trace surfaces opnum + size.
- crates/mxaccess-compat/tests/buffered_subscribe_live.rs — F49 step 1
  live test that drives subscribe_buffered + a 500ms-cadence writer.
  Also pulls tracing-subscriber as a dev-dep so the test can dump
  router activity.

Existing router_task_decodes_callback_invoked_into_broadcast unit test
updated to wrap its synthetic 0x32 body in an envelope so the new
parse path actually accepts it.

Live result: F56 — the buffered round-trip *registers* successfully
(RegisterReference returns HRESULT 0; engine sends one 0x11
RegistrationResult + one 51-byte op-status per write, perfectly
clocked) but the engine never sends a 0x33 DataUpdate. Rust-port-
specific gap vs the .NET reference's working buffered path; root
cause is likely a field-level difference in the RegisterReference
body or a missing post-RegisterReference step. Captured as F56 in
design/followups.md, blocking F49 step 1; F56's DoD is the same
live test reporting >=3 DataChange arrivals.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

rust/Cargo.lock

@@ -19,6 +19,15 @@ dependencies = [
  "cpufeatures",
 ]
 
+[[package]]
+name = "aho-corasick"
+version = "1.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ddd31a130427c27518df266943a5308ed92d4b226cc639f5a8f1002816174301"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "async-trait"
 version = "0.1.89"
@@ -421,6 +430,12 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "lazy_static"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bbd2bcb4c963f2ddae06a2efc7e9f3591312473c50c6685e1f298068316e66fe"
+
 [[package]]
 name = "libc"
 version = "0.2.186"
@@ -433,6 +448,15 @@ version = "0.4.29"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
 
+[[package]]
+name = "matchers"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d1525a2a28c7f4fa0fc98bb91ae755d1e2d1505079e05539e35bc876b5d65ae9"
+dependencies = [
+ "regex-automata",
+]
+
 [[package]]
 name = "md-5"
 version = "0.10.6"
@@ -583,6 +607,8 @@ dependencies = [
  "thiserror 2.0.18",
  "tokio",
  "tokio-stream",
+ "tracing",
+ "tracing-subscriber",
 ]
 
 [[package]]
@@ -628,6 +654,15 @@ dependencies = [
  "windows",
 ]
 
+[[package]]
+name = "nu-ansi-term"
+version = "0.50.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7957b9740744892f114936ab4a57b3f487491bbeafaf8083688b16841a4240e5"
+dependencies = [
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "num-bigint"
 version = "0.4.6"
@@ -812,6 +847,23 @@ dependencies = [
  "cipher 0.5.1",
 ]
 
+[[package]]
+name = "regex-automata"
+version = "0.4.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e1dd4122fc1595e8162618945476892eefca7b88c52820e74af6262213cae8f"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc897dd8d9e8bd1ed8cdad82b5966c3e0ecae09fb1907d58efaa013543185d0a"
+
 [[package]]
 name = "ring"
 version = "0.17.14"
@@ -939,6 +991,15 @@ dependencies = [
  "digest",
 ]
 
+[[package]]
+name = "sharded-slab"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f40ca3c46823713e0d4209592e8d6e826aa57e928f09752619fc696c499637f6"
+dependencies = [
+ "lazy_static",
+]
+
 [[package]]
 name = "shlex"
 version = "1.3.0"
@@ -957,6 +1018,12 @@ version = "0.4.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0c790de23124f9ab44544d7ac05d60440adc586479ce501c1d6d7da3cd8c9cf5"
 
+[[package]]
+name = "smallvec"
+version = "1.15.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
+
 [[package]]
 name = "socket2"
 version = "0.6.3"
@@ -1024,6 +1091,15 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "thread_local"
+version = "1.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f60246a4944f24f6e018aa17cdeffb7818b76356965d03b07d6a9886e8962185"
+dependencies = [
+ "cfg-if",
+]
+
 [[package]]
 name = "tiberius"
 version = "0.12.3"
@@ -1144,6 +1220,36 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "db97caf9d906fbde555dd62fa95ddba9eecfd14cb388e4f491a66d74cd5fb79a"
 dependencies = [
  "once_cell",
+ "valuable",
+]
+
+[[package]]
+name = "tracing-log"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee855f1f400bd0e5c02d150ae5de3840039a3f54b025156404e34c23c03f47c3"
+dependencies = [
+ "log",
+ "once_cell",
+ "tracing-core",
+]
+
+[[package]]
+name = "tracing-subscriber"
+version = "0.3.23"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cb7f578e5945fb242538965c2d0b04418d38ec25c79d160cd279bf0731c8d319"
+dependencies = [
+ "matchers",
+ "nu-ansi-term",
+ "once_cell",
+ "regex-automata",
+ "sharded-slab",
+ "smallvec",
+ "thread_local",
+ "tracing",
+ "tracing-core",
+ "tracing-log",
 ]
 
 [[package]]
@@ -1174,6 +1280,12 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "valuable"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba73ea9cf16a25df0c8caa16c51acb937d5712a8429db78a3ee29d5dcacd3a65"
+
 [[package]]
 name = "version_check"
 version = "0.9.5"