Bun parity verification: reconcile legacy unsupported ICU assertion

The pinned original test/js/node/process/process.test.js:321 requires process.binding("icu") to throw. Home's native ICU binding is implemented and verified under #862, including conversion/streaming decoding/transcode/width and per-process identity.

The unchanged process file currently records 101 passes, one failure, one skip and three TODOs; its failure is the unsupported-ICU expectation. The implementation returns the real ICU API, so it cannot also throw for this assertion without test-dependent behavior or removal of the implemented capability.

Reconcile this historical unsupported-capability assertion with logical full-feature parity. Preserve the current original failure evidence and keep it separate from green process/OS checks. Do not branch behavior on filenames or patch assertions merely to claim 100% coverage.

Parent: #66. Related native ICU implementation/platform tracker: #862.

Process binding/OS contracts checkpoint (2026-10-10, broad scope retains failure): source f8068cbf0 and verified evidence. Six native bindings execute from Home, including standalone constants/UV; 12/12 selected source/header files match the pin with exact ABI/cache validation. Config reports actual backend FIPS/pointer width and config/X509 bindings retain private per-process identity. OS priority validates types/ranges before system calls and normalizes permission diagnostics; userInfo reads actual libuv account data, propagates option getters and supports buffer encoding. Initial priority/getter original failures are cleared. Fourteen original files: 167 passes plus nine process checks, one registered failure/one failed file, one skip, three TODOs and one skipped file. The sole failure is the legacy ICU-unsupported assertion tracked by #872; actual ICU functionality is retained, with no filename-conditioned behavior or assertion edits. Fourteen native groups, changed ownership/ABI 14 tests / 718 assertions and Debug 38/38 pass. Build peak 5,653 MB under 8,192 MB; ownership 409 MB, originals 210 MB under 3,840 MB. 211 committed archives verify and 14 reports restore their recorded outcomes, including the failure. Compile/producer failures remain without passing credit. Broader process/OS/binding stubs, ICU expectation reconciliation, complete suite and Release/ASAN/all-platform parity remain unfinished.