libdatadog removed the libdd-http-client crate in v36; it no longer ships
in v37. Remove the native http_client module and all its dependents:

- Delete src/native/http_client/ (client, response, errors, mod)
- Remove mod/register_http_client from lib.rs
- Remove enable_client_side_stats_obfuscation from data_pipeline/mod.rs
  (stats-obfuscation feature merged into libdd-data-pipeline defaults)
- Remove HTTPClient, HttpResponse, HttpClientError and subclasses from
  _native.pyi and ddtrace/internal/native/__init__.py
- Delete ddtrace/internal/http_client.py and its tests

The HTTPClient had no production callers outside its own wrapper module.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

stats-obfuscation is now on by default in libdatadog v37; the
enable_client_side_stats_obfuscation() builder method no longer exists.
Remove the call from TraceExporterWriter.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

…bfuscation feature

The method still exists in libdatadog v37 but requires the stats-obfuscation
feature on libdd-data-pipeline. Re-add the feature flag and restore the
PyO3 wrapper, Python stub, and writer call that were incorrectly removed.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

libdd-http-client still exists in v37 — it was redesigned, not removed.
Restore the http_client Rust module rewritten for the v37 API:

- HttpClient::new() no longer takes a runtime; BlockingRuntime trait
  (not SharedRuntime) provides block_on — update imports accordingly
- Arc<ForkSafeRuntime> replaces Arc<SharedRuntime> (SharedRuntime is
  now a trait in v37; ForkSafeRuntime is the concrete type)
- Re-add libdd-http-client, bytes, url deps to Cargo.toml
- Restore mod http_client and register_http_client in lib.rs
- Restore ddtrace/internal/http_client.py and its test suite
- Restore HTTPClient, HttpResponse, HttpClientError and subclasses in
  _native.pyi and ddtrace/internal/native/__init__.py
- Add missing Iterable import to _native.pyi

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

The merged libdatadog FFE remaps per-flag config parse failures (bad regex,
variant type mismatch) from ConfigurationParseError to the new
FlagConfigurationInvalid variant. dd-trace-py's From<EvaluationError> match
didn't handle it, so it fell through to ErrorCode::General and the
feature_flag.evaluations metric reported error.type=general instead of
parse_error, failing the FEATURE_FLAGGING_AND_EXPERIMENTATION system tests.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

Co-authored-by: Munir Abdinur <[email protected]>

Restore the bytes 1.10+ comment and the original ordering of url and
libdd-http-client that were cosmetically changed during the v37 bump.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

… arm

Both map to PARSE_ERROR; combine them into a single match arm.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

…client

The code review suggestion incorrectly reverted the import back to
SharedRuntime (a v37 trait), but the struct holds Arc<ForkSafeRuntime>
and block_on requires BlockingRuntime in scope.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

…ew()

ForkSafeRuntime::new() is a trait method from SharedRuntime; without the
trait in scope the compiler cannot resolve it.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

With collect_all_threads enabled (default in v37), the receiver uses
PTRACE_SEIZE + PTRACE_INTERRUPT on the crashing thread, which interrupts
poll() in wait_for_pollhup with EINTR. When crashing from a dynamically-
loaded C++ extension on Python 3.14, repeated EINTR prevents the 5-second
timeout from expiring, causing an indefinite hang.

Consistent with the existing pattern of Python 3.14 crashtracker skips
("Stack v2 not supported on 3.14") in 9d9bd80.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

…-v37

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

…d from ptrace

The receiver in v37 began ptracing the crashing thread
(crashing_tid) as part of collect_all_threads. That thread is blocked
in poll() inside its signal handler on the alternate signal stack; the
resulting PTRACE_INTERRUPT issues EINTR in a loop, causing the receiver
to hang indefinitely on CPython 3.14.

Pin all libdatadog deps to commit 504ea9d7 on the fix branch, which
restores the v35 behaviour of excluding crashing_tid from
stream_thread_contexts. With the fix in place the 3.14 skip is no
longer needed.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

…ng thread from ptrace"

This reverts commit 52fa5a9.

… 'return True' path is only hit when OTLP trace export is enabled AND there's no user-configured DD Trace protocol version.

…ce-compatibility

…ation variable to '_otel_trace_semantics_enabled'

…ith upstream

…re serialization.

…request" for client spans

…bling trace native span events when OTLP export is enabled