feat(dev): add Windows cross-build support

[thieman]

pls look toby

With this PR it's now possible to cross-compile ADP-for-Windows on a Mac. Nothing is actually runnable but I wanted to get this sorted before I started working on Windows CI.

I scoped this to only saluki and agent-data-plane, testing tools like correctness are not in scope and probably still don't build on Windows. I'm not planning on running correctness but if any of those have problems I'll get to them as part of the CI PR.

Summary

• Add Windows platform settings with Core Agent-compatible ConfigRoot registry lookup and ProgramData fallback paths.
• Add local macOS Windows cross-build setup/build targets using cargo-xwin and Homebrew LLVM.
• Fix Windows cfg/build blockers across networking, workload helpers, correctness tools, and ADP so the workspace cross-builds for x86_64-pc-windows-msvc.

Notes

• This does not add Windows runtime support for ADP service management, named pipes, or Windows-specific DogStatsD ingestion.
• Unix socket address types remain available for config/type handling, but Unix socket listener construction returns an unsupported-platform error on non-Unix platforms.

Test plan

• make fmt
• cargo check --workspace
• cargo check --workspace --tests
• make build-windows-cross
• PATH="/opt/homebrew/opt/llvm/bin:$PATH" cargo xwin check --target x86_64-pc-windows-msvc --workspace --tests
• pre-commit checks run by git commit

[pr-commenter]

Binary Size Analysis (Agent Data Plane)

Baseline: 08cd4c4 · Comparison: 4aa3ff2 · diff
Analysis Configuration: stripped binaries · Pass/Fail Threshold: +5%
Sizes: 37.93 MiB (baseline) vs 37.91 MiB (comparison)
Size Change: -20.49 KiB (-0.05%)

✅ Binary size difference within threshold

Changes by Module

Module	File Size	Symbols
core	-18.78 KiB	1790
tokio	-16.27 KiB	876
agent_data_plane::main::_{{closure}}	+15.63 KiB	1
alloc	-10.79 KiB	190
[sections]	-5.73 KiB	7
ottl::parser::arena	+5.52 KiB	7
std	+5.23 KiB	56
serde_yaml	-5.04 KiB	17
h2	-4.60 KiB	45
[Unmapped]	+4.46 KiB	1
tonic	-4.17 KiB	94
agent_data_plane::cli::run	-3.39 KiB	8
anon.d79fab06779a07988ddcf6c4bb681b9d.2.llvm.17162878208440994959	+3.06 KiB	1
hashbrown	-2.95 KiB	17
anon.acbd287db64895e155c57ba7daeb669a.166.llvm.16512133253778547288	-2.88 KiB	1
anon.36eead261da73468b10600f578de22ed.87.llvm.14046994766694184360	-2.83 KiB	1
anon.aff4687329d0c87eda2031b0ab3e4b27.13.llvm.18013086268746836388	+2.82 KiB	1
http	+2.74 KiB	20
agent_data_plane::internal::remote_agent	+2.69 KiB	10
tonic_prost	-2.60 KiB	16

Detailed Symbol Changes

    FILE SIZE        VM SIZE    
 --------------  -------------- 
 +20e2% +16.9Ki +24e2% +16.9Ki    agent_data_plane::state::metrics::rules::get_datadog_agent_remappings::hbdc0274dbd81cbc3
   +47% +15.6Ki   +47% +15.5Ki    agent_data_plane::main::_{{closure}}::h91f918e534067526
  [NEW] +12.9Ki  [NEW] +12.8Ki    agent_data_plane::state::metrics::rules::get_compat_remappings::h08bf766045445756
   +83% +4.46Ki  [ = ]       0    [Unmapped]
  [NEW] +3.76Ki  [NEW]    +340    core::ptr::drop_in_place<http_body_util::combinators::map_err::MapErr<http_body_util::combinators::map_frame::MapFrame<tonic::body::Body,tonic::codec::decode::Streaming<datadog_protos::agent_include::datadog::remoteagent::flare::v1::GetFlareFilesRequest>::new<tonic::body::Body,tonic_prost::codec::ProstDecoder<datadog_protos::agent_include::datadog::remoteagent::flare::v1::GetFlareFilesRequest>>::{{closure}}>,tonic::codec::decode::Streaming<datadog_protos::agent_include::datadog::remoteagent::flare::v1::GetFlareFilesRequest>::new<tonic::body::Body,tonic_prost::codec::ProstDecoder<datadog_protos::agent_include::datadog::remoteagent::flare::v1::GetFlareFilesRequest>>::{{closure}}>>::h2fb85ccecc1cb926
  [NEW] +3.44Ki  [NEW]    +456    core::ptr::drop_in_place<core::iter::adapters::map::Map<std::collections::hash::map::IntoIter<axum::routing::RouteId,axum::routing::Endpoint<saluki_components::sources::dogstatsd::replay::replay_control::DogStatsDReplayControl>>,axum::routing::path_router::PathRouter<saluki_components::sources::dogstatsd::replay::replay_control::DogStatsDReplayControl,_>::with_state<$LP$$RP$>::{{closure}}>>::h3735a674b182d336
  [NEW] +3.06Ki  [NEW]     +74    anon.d79fab06779a07988ddcf6c4bb681b9d.2.llvm.17162878208440994959
  [NEW] +2.84Ki  [NEW]     +47    _<http_body_util::combinators::map_err::MapErr<B,F> as http_body::Body>::size_hint::h7a2146171ab2c5b8
  +182% +2.83Ki  +195% +2.83Ki    h2::proto::streams::streams::StreamRef<B>::send_data::hb2e588f364643831
 -62.4% -2.85Ki -64.4% -2.83Ki    serde_yaml::value::ser::_<impl serde_core::ser::Serialize for serde_yaml::value::Value>::serialize::h7e3b3ab711e7b79b
  [DEL] -2.88Ki  [DEL]     -74    anon.acbd287db64895e155c57ba7daeb669a.166.llvm.16512133253778547288
  -2.0% -3.08Ki  -2.0% -3.08Ki    agent_data_plane::cli::run::handle_run_command::_{{closure}}::hdf07f62ba689f516
  -0.3% -3.59Ki  -0.3% -3.59Ki    [section .gcc_except_table]
 -37.9% -3.70Ki -38.3% -3.70Ki    h2::codec::framed_write::Encoder<B>::buffer::h1657e6f3d78b394a
 -81.6% -4.02Ki -32.6%    -333    core::ptr::drop_in_place<tonic::body::Body>::hce9d1d3f74301fef
  [DEL] -4.25Ki  [DEL] -4.12Ki    agent_data_plane::state::metrics::rules::aggregation::get_aggregation_remappings::h8df5781a6f761921
  [DEL] -4.40Ki  [DEL] -4.28Ki    agent_data_plane::state::metrics::rules::transaction::get_transaction_remappings::h7a9643623e71d5ed
  [DEL] -9.38Ki  [DEL] -9.26Ki    agent_data_plane::state::metrics::rules::dogstatsd::get_dogstatsd_remappings::h4c255c759e1d8868
  [DEL] -12.4Ki  [DEL] -12.3Ki    agent_data_plane::state::metrics::rules::compat::get_compat_remappings::ha0b8e71d70c4a783
  [DEL] -17.7Ki  [DEL] -17.6Ki    tokio::runtime::park::CachedParkThread::block_on::hf364174df10d3359
  -0.3% -18.1Ki  -0.1% -4.25Ki    [9379 Others]
  -0.1% -20.5Ki  -0.1% -16.5Ki    TOTAL

[pr-commenter]

Regression Detector (Agent Data Plane)

Run ID: da08f783-def0-4b07-8517-47a2bcc816ea
Baseline: 08cd4c40 · Comparison: 4aa3ff26 · diff

Optimization Goals: ✅ No significant changes detected

Fine details of change detection per experiment (35)

Experiments configured erratic: true are tagged (ignored) and skipped when determining which experiments regressed or improved. Experiments which are detected as erratic at runtime are tagged (erratic) to flag that the run's sample dispersion was high, but their regression / improvement signal still counts.

experiment	goal	Δ mean %	links
dsd_uds_10mb_3k_contexts_cpu (erratic)	cpu	⚪ +2.52	metrics profiles logs
dsd_uds_500mb_3k_contexts_throughput	throughput	⚪ -2.05	metrics profiles logs
dsd_uds_100mb_3k_contexts_cpu (erratic)	cpu	⚪ +1.90	metrics profiles logs
otlp_ingest_traces_ottl_filtering_5mb_cpu (erratic)	cpu	⚪ +0.63	metrics profiles logs
quality_gates_rss_dsd_medium	memory	⚪ +0.48	metrics profiles logs
otlp_ingest_traces_ottl_transform_5mb_cpu (erratic)	cpu	⚪ +0.39	metrics profiles logs
quality_gates_rss_idle	memory	⚪ +0.18	metrics profiles logs
quality_gates_rss_dsd_ultraheavy	memory	⚪ +0.09	metrics profiles logs
dsd_uds_100mb_3k_contexts_memory	memory	⚪ +0.04	metrics profiles logs
otlp_ingest_traces_5mb_memory	memory	⚪ +0.04	metrics profiles logs
dsd_uds_512kb_3k_contexts_memory	memory	⚪ +0.04	metrics profiles logs
otlp_ingest_logs_5mb_throughput (ignored)	throughput	⚪ -0.02	metrics profiles logs
dsd_uds_10mb_3k_contexts_throughput	throughput	⚪ -0.01	metrics profiles logs
dsd_uds_1mb_3k_contexts_throughput	throughput	⚪ -0.00	metrics profiles logs
dsd_uds_512kb_3k_contexts_throughput	throughput	⚪ +0.00	metrics profiles logs
otlp_ingest_metrics_5mb_cpu (erratic)	cpu	⚪ -0.00	metrics profiles logs
dsd_uds_100mb_3k_contexts_throughput	throughput	⚪ +0.00	metrics profiles logs
otlp_ingest_logs_5mb_cpu (ignored)	cpu	⚪ -0.01	metrics profiles logs
otlp_ingest_metrics_5mb_throughput	throughput	⚪ +0.02	metrics profiles logs
otlp_ingest_traces_5mb_throughput	throughput	⚪ +0.04	metrics profiles logs
otlp_ingest_traces_ottl_transform_5mb_throughput	throughput	⚪ +0.07	metrics profiles logs
quality_gates_rss_dsd_low	memory	⚪ -0.08	metrics profiles logs
otlp_ingest_traces_ottl_filtering_5mb_memory	memory	⚪ -0.09	metrics profiles logs
otlp_ingest_traces_ottl_filtering_5mb_throughput	throughput	⚪ +0.11	metrics profiles logs
dsd_uds_1mb_3k_contexts_memory	memory	⚪ -0.18	metrics profiles logs
otlp_ingest_traces_ottl_transform_5mb_memory	memory	⚪ -0.19	metrics profiles logs
dsd_uds_500mb_3k_contexts_memory	memory	⚪ -0.26	metrics profiles logs
dsd_uds_10mb_3k_contexts_memory	memory	⚪ -0.31	metrics profiles logs
quality_gates_rss_dsd_heavy	memory	⚪ -0.48	metrics profiles logs
dsd_uds_1mb_3k_contexts_cpu (erratic)	cpu	⚪ -0.53	metrics profiles logs
dsd_uds_500mb_3k_contexts_cpu (erratic)	cpu	⚪ -0.89	metrics profiles logs
otlp_ingest_logs_5mb_memory (ignored)	memory	⚪ -0.92	metrics profiles logs
otlp_ingest_metrics_5mb_memory	memory	⚪ -0.97	metrics profiles logs
otlp_ingest_traces_5mb_cpu (erratic)	cpu	⚪ -2.11	metrics profiles logs
dsd_uds_512kb_3k_contexts_cpu (erratic)	cpu	🟢 -6.46	metrics profiles logs

Bounds Checks: ✅ Passed (5)

experiment	check	replicates	observed	links
quality_gates_rss_dsd_heavy	memory_usage	10/10	✅ 128 MiB ≤ 140 MiB	metrics profiles logs
quality_gates_rss_dsd_low	memory_usage	10/10	✅ 39.9 MiB ≤ 50 MiB	metrics profiles logs
quality_gates_rss_dsd_medium	memory_usage	10/10	✅ 61.7 MiB ≤ 75 MiB	metrics profiles logs
quality_gates_rss_dsd_ultraheavy	memory_usage	10/10	✅ 183 MiB ≤ 200 MiB	metrics profiles logs
quality_gates_rss_idle	memory_usage	10/10	✅ 26.7 MiB ≤ 40 MiB	metrics profiles logs

Explanation

A change is flagged as a regression when |Δ mean %| > 5.00% in the regressing direction for its optimization goal AND SMP marks the experiment as a regression (is_regression: true). Improvements use the matching criteria for the improving direction. Experiments configured erratic: true (tagged (ignored)) are skipped outright; experiments detected as erratic at runtime (tagged (erratic)) still count, since that flag describes sample dispersion rather than directional certainty. The Δ mean % cell is colored accordingly: 🟢 = improvement, 🔴 = regression, ⚪ = neutral. Reduction in CPU or memory is an improvement; reduction in ingress throughput is a regression.

[thieman]

Adding this for now as a way to locally test Windows support. May remove this once we have Windows CI working

[thieman]

This file is vibed from the core agent impl but untested as we don't actually have tests running yet. Added a TODO to come back and add tests.