feat: add GetBusinessProfile

[pradosystems]

What

Exposes whatsmeow's GetBusinessProfile, returning the public information a
WhatsApp Business account chose to publish:

profile = client.get_business_profile(build_jid("5511999999999"))
profile.Email
profile.Address
profile.Categories          # [{ID, Name}]
profile.BusinessHoursTimeZone
profile.BusinessHours       # [{DayOfWeek, Mode, OpenTime, CloseTime}]

Why

There is currently no way to reach this from neonize. resolve_business_message_link
only works from a wa.me/message/... link and returns a different, smaller
shape (BusinessMessageLinkTarget), so it does not cover the case of "I have a
JID, what does this business publish?".

It is not reachable via ctypes either — the shipped .so only exports
PutBusinessName and ResolveBusinessMessageLink:

$ nm -D neonize-linux-amd64.so | grep -i business
T PutBusinessName
T ResolveBusinessMessageLink

How

Follows the existing GetProfilePicture pattern end to end:

file	change
goneonize/Neonize.proto	BusinessProfile, Category, BusinessHoursConfig, GetBusinessProfileReturnFunction
goneonize/utils/encoder.go	EncodeBusinessProfile / EncodeCategory / EncodeBusinessHoursConfig
goneonize/main.go	//export GetBusinessProfile
neonize/_binder.py	ctypes signature
neonize/client.py	get_business_profile()
neonize/exc.py	GetBusinessProfileError

Two notes on keeping the diff reviewable:

• New messages were appended at the END of Neonize.proto on purpose. Adding
  them in the middle shifts every following message's descriptor index, which
  alone produced a ~1150-line diff in the regenerated .pb.go. Appending keeps
  it at ~350 lines, almost all of it the new types.
• Generated files were regenerated with the same toolchain the repo already
  uses — protoc 34.1 and protoc-gen-go v1.36.12 — matching the headers of
  the committed files, so no unrelated churn.

Verification

$ CGO_ENABLED=1 go build -buildmode=c-shared -ldflags=-s -o neonize.so
$ nm -D neonize.so | grep -i "T GetBusinessProfile"
000000000081d4a0 T GetBusinessProfile

I have not added the async variant in aioze/client.py — happy to add it if you
prefer the two kept in sync in the same PR.