test(agc): fix the stale 32-bit WriteWait expectation and run the full suite

[Dextroid17]

What

Fixes the stale expectation in testMemory and registers the full agc_command_tests mode in ctest. Closes #1005.

WriteWait truncates the reference and mask of a 32-bit wait (size == 0) to their low halves since 9c2a756 ("relaxed checks for what titles send"), but testMemory still expected a reference above 32 bits to throw, so the binary failed when run without arguments:

$ ./build/tests/agc_command_tests
expected an exception

Only agc_initialization (agc_command_tests defaults) is registered in ctest, so the stale expectation went unnoticed and the packet, marker, flip, register and memory cases have not been running.

• testMemory: the second expectFailure becomes an assertion that the packet keeps the low halves of the reference and mask (0x100000000 → 0, 0xffffffff00000001 → 1). The storage.words == before check now covers only the remaining sceAgcWaitRegMemPatchReference failure.
• CMakeLists.txt: add agc_commands (agc_command_tests with no arguments) next to agc_initialization, so the full mode runs in CI.

Tested

• Linux, CachyOS (Arch), GCC 16.2.1, Release.
• Before: ./build/tests/agc_command_tests → expected an exception, exit 1.
• After: AGC command tests passed, exit 0.
• ctest -R '^agc_(initialization|commands)$' → both pass.
• Full suite: ctest --test-dir build -j 8 --timeout 120 → 370/370 pass.
• Not tested on a title.

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 in TechnicalDebt
• 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 — not applicable
• Generic behaviour, not specific to one title
• Depends on: none
• AI-assisted: yes