Port gRPC outlier detection policy

Scope

Port Bun corpus position 3985, js/third_party/grpc-js/test-outlier-detection.test.ts (26 active tests).

Required contracts

• validate interval/base/max ejection durations and percentage fields
• reject incompatible pick_first child policies
• resolve and round-robin across ipv4:///host:port,... targets
• track per-endpoint successes and failures
• eject endpoints under success-rate and failure-percentage policies
• restore endpoints after the configured ejection window
• clean up servers bound to multiple addresses
• retain parse/ejection causes with policy path, endpoint, operation, and source-module stack context

Verification

• all 26 focused upstream tests pass without unsupported cases
• permanent diagnostics cover validation context and endpoint lifecycle
• existing gRPC, SQL adapter, and third-party gates remain green

Implemented and pushed in c4b4f3043.

Completed contracts:

• validated interval, base/max ejection durations, and percentage fields
• rejected incompatible pick_first child policies
• resolved and round-robined across ipv4:///host:port,... targets
• tracked per-endpoint successes and failures
• ejected failing endpoints for success-rate and failure-percentage policies
• restored endpoints after the configured virtual-clock ejection window
• cleaned every registration for servers bound to multiple ports
• parse failures retain causes with policy path and source-module stack context

Verification:

• focused Bun corpus: 26 passed, 0 failed, 0 todo, 0 unsupported
• permanent gRPC diagnostics: 12 passed
• SQL adapter contracts: passed
• permanent third-party JWT/utility mini-suite: passed
• zig fmt --check and git diff --check: passed

Cumulative through position 3985: 327 files, 2,719 passed, 209 todo, 0 failed, 0 unsupported, 171 allowed-empty.