[MarrasFederico]

What

sceNpMatching2GetUserInfoList threw for every call. Firmware 13.42, run natively in #12623, showed an order unlike the other requests: a null parameter (0x80550C0A), then the context, then the parameter contents. A zeroed parameter gave CONTEXT_NOT_FOUND (0x80550C06) on an unknown context, 0x80550C3B on the A context 258, and INVALID_SERVER_ID (0x80550C0C) on context 1.

The export now follows that order: not initialized, null request or request id, unknown context, A context (0x80550C3B, INVALID_CONTEXT in shadPS4's np_error.h), then server id 0. A request that passes them still throws: the run did not show how an accepted request completes offline.

• The initialization check first and the null request id check are not in the measurement; they follow the other request calls and shadPS4.
• The signature matches the other request calls; sceNpMatching2GetUserInfoListA is unchanged.

Not measured on a console.

Tested

Ubuntu 26.04.1, kernel 7.0.0, GCC 15.2.0, Release, BUILD_TESTING=ON, on main 6e6dae4e8b. Windows and macOS were not compiled here. No title was run.

• guest_np_matching2_offline passes. New cases: before initialization; a null request on known and unknown contexts; a null request id; a zeroed request on context 99, on the A context and on context 1.
• Main's body (an unconditional throw) aborts the new test. Removing only the A-context check fails at an A context did not return 0x80550C3B; restoring it passes.
• check_conventions.py --base upstream/main passes.
• pr_overlap.py: #15476 adds test cases next to these in GuestNpMatching2Offline.cpp, without implementing this export; that hunk needs a merge whichever lands second. My #16109 adds its debt line and tests in the same spots. #14212 only respaces the debt file.

Checklist

• Based on current main; no other open PR implements the same functions
• One topic per PR; follow-ups go in a new PR
• No comments in code except technical debt
• Unimplemented paths throw (NotImplemented_nid_no_patch); silent stubs are listed under Silent stubs in their library's technical debt file
• No notes, investigation .md files or images added to the repository (attach them to this PR)
• New third-party code is a submodule built from source
• Generic behaviour, not specific to one title
• Depends on: none
• Fixes: none
• Unblocks: none
• GPUs tested: n/a
• AI-assisted: yes