Check when a HRESULT is a Win32 code and fetch it

[zeroSteiner]

This fixes an error that was privately reported to me where Metasploit's icpr_cert module was not fetching an error code and then crashing with a stack trace because the HRESULT definition didn't exist. The code in question was 0x80070547 which should map to the win32 ERROR_CANT_ACCESS_DOMAIN_INFO code.

There's also some extra require statements, so consumers can just require 'windows_error/h_result'.

[Copilot]

Pull request overview

Adds Win32-aware HRESULT lookup so callers can resolve FACILITY_WIN32 HRESULTs (e.g., 0x80070547) to the underlying Win32 error code, and makes it easier to require submodules directly.

Changes:

• Ensure windows_error/win32 and windows_error/nt_status can be required standalone by requiring the base windows_error definitions.
• Add Facility.find_by_h_result and harden facility constant iteration to only consider FacilityCode instances.
• Teach HResult.find_by_retval to detect FACILITY_WIN32 and delegate to Win32.find_by_retval(retval & 0xffff).

Impact Analysis:

• Blast radius: medium; affects consumers of WindowsError::HResult.find_by_retval and anyone requiring windows_error/h_result, plus standalone require paths for windows_error/win32 and windows_error/nt_status.
• Data and contract effects: HResult.find_by_retval may now return Win32 WindowsError::ErrorCode instances (not HResultCode) for FACILITY_WIN32 HRESULTs, which changes the effective return-type contract for that method.
• Rollback and test focus: rollback is straightforward (revert), but validation should focus on FACILITY_WIN32 mapping cases (e.g., 0x80070547 -> ERROR_CANT_ACCESS_DOMAIN_INFO) and confirming non-WIN32 HRESULT lookups remain unchanged.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
lib/windows_error/win32.rb	Require base library so Win32 constants can be loaded via standalone require.
lib/windows_error/nt_status.rb	Require base library so NTSTATUS constants can be loaded via standalone require.
lib/windows_error/h_result/facility.rb	Add find_by_h_result and skip non-FacilityCode constants during lookup.
lib/windows_error/h_result.rb	Require Win32 and map FACILITY_WIN32 HRESULTs to Win32 error codes.

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