fix: decode the Guide button bit in decodeXInput360 (XInput-360 family)

[MichaelWilsonSNC]

Description

decodeXInput360 (the shared decoder for every Parser::XINPUT_360 /
XINPUT_360_WIRELESS device in the kKnown table — genuine Xbox 360
controllers and its many licensed clones, plus the Amazon Luna
Controller) never read byte 3 bit 0x04 of the wired report. That bit
is the standard Guide/Xbox button position in the XInput wired
protocol (the same bit Linux's xpad driver treats as BTN_MODE); the
other bits in that byte (0x01/0x02 bumpers, 0x10..0x80 face
buttons) were already decoded, but 0x04 was dead, so any pad's
center/Guide button silently produced no input at all instead of
XUSB_GUIDE.

Found on real hardware: a live raw-report capture from an Amazon Luna
Controller (USB VID:PID 1949:041A, wired mode, from #153) showed
byte 3 going to exactly 0x04 and nothing else when its center button
was pressed, with A/B/X/Y independently confirmed against their own
existing bits (0x10/0x20/0x40/0x80) in the same capture. Fix is
a single added line, decoding that bit the same way every other button
in the function already is, with no change to the report layout or any
other bit.

No wire-protocol changes; nothing to coordinate with satellite,
dish-linux, or dish-mac.

Scope note for review: this is a generic decoder fix, not a Luna-only
special case, so it affects every device riding XINPUT_360/
XINPUT_360_WIRELESS in kKnown (Mad Catz, PDP, Hori, PowerA,
Afterglow, dance pads, fight sticks, etc.). Pads without a physical
Guide button never assert that bit in hardware, so this is a no-op for
them. The only theoretical residual risk is an unlicensed clone that
reused bit 0x04 for some other custom function instead of leaving it
unused; if one exists, worst case is that button now also raises
Guide/Home, not a crash or corrupted input.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing
  functionality to not work as expected)
• Refactor (code change that neither fixes a bug nor adds a feature)
• Documentation update

How Has This Been Tested?

• Unit tests
• Instrumented tests
• Manual testing on device/emulator

Added Decode.Xbox360WiredGuideButtonSetsGuideBit to
usb_parsers_test.cpp, asserting byte 3 0x04 sets XUSB_GUIDE
through decodeReport(Parser::XINPUT_360, ...). Full native host
suite: 241/241 passing (ctest across all app/src/test/cpp binaries).

Manual testing: real Amazon Luna Controller, wired directly to an
Android phone running dish, Direct mode. Captured raw USB interrupt
reports for A/B/X/Y and the center button before the fix (center
button produced no bit at all in wButtons); after the fix, rebuilt
and reinstalled the app and confirmed the center button now reaches
the Guide/Home action end-to-end through a satellite host.

Checklist

• My code follows the project's style guidelines (ktlint/detekt
  untouched — no Kotlin changed; clang-format skipped locally, not
  installed at the pinned 22.1.4 version, but the change is a
  single line matching the exact formatting of every neighboring
  line in the same if chain, and CI's own clang-format gate will
  catch it if not)
• I have performed a self-review of my code
• Any non-obvious code explains why, not what (no comment added —
  the fix reads identically to every other bit check in the same
  function, so a comment here would be inconsistent with the rest
  of the file)
• I have made corresponding changes to documentation
  (CHANGELOG.md, under [Unreleased])
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my
  feature works
• New and existing unit tests pass locally with my changes
  (241/241 native host tests, assembleDebug)