checker: byte deprecation doesn't trigger for []byte in struct field or fn param

[Le0Developer]

V version: V 0.5.0 75fc8be, press to see full `v doctor` output

V full version	V 0.5.0 75fc8be
OS	macos, macOS, 26.2, 25C56
Processor	10 cpus, 64bit, little endian, Apple M4
Memory	1GB/16GB
V executable	/Users/leodev/p/v/v/v
V last modified time	2026-01-31 10:45:14
V home dir	OK, value: /Users/leodev/p/v/v
VMODULES	OK, value: /Users/leodev/.vmodules
VTMP	OK, value: /tmp/v_501
Current working dir	OK, value: /Users/leodev/p/v/test
Git version	git version 2.52.0
V git status	weekly.2026.05-80-g75fc8bed
.git/config present	true
cc version	Apple clang version 17.0.0 (clang-1700.0.13.3)
gcc version	Apple clang version 17.0.0 (clang-1700.0.13.3)
clang version	Apple clang version 17.0.0 (clang-1700.0.13.3)
tcc version	tcc version 0.9.28rc 2026-01-10 HEAD@5ec0e6f8 (AArch64 Darwin)
tcc git status	thirdparty-macos-arm64 f995efa3
emcc version	N/A
glibc version	N/A

What did you do?
./v -g -o vdbg cmd/v && ./vdbg repro.v && repro

struct Test {
  foo byte // byte is deprecated, use u8 instead
  bar []byte // no warning!
}

What did you see?

repro.v:2:7: error: byte is deprecated, use u8 instead
    1 | struct Test {
    2 |   foo byte // byte is deprecated, use u8 instead
      |       ~~~~
    3 |   bar []byte // no warning!
    4 | }

What did you expect to see?

Warning for using []byte

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[JalonSolov]

Not this only fails for struct fields, so I changed the title to clarify. Works as expected for regular vars.

[Le0Developer]

This also fails for function arguments.

[JalonSolov]

Hmm... I see.

fn foo(b []byte) {
        println(b)
}

foo([]byte{})

only shows one warning, on the call

x.v:5:7: error: byte is deprecated, use u8 instead
    3 | }
    4 | 
    5 | foo([]byte{})
      |       ~~~~

when it should also show it on the fn declaration.