feat: make bot node injection configurable via NEONIZE_BOT_TAG

[ConTresillo]

Summary

Makes the <bot biz_bot="1"/> node injection in GenerateWABinary configurable at runtime through the NEONIZE_BOT_TAG environment variable, instead of being hardcoded to always-on for private chats.

Changes

• goneonize/main.go: added shouldAddBotNode(isPrivate bool) helper that reads NEONIZE_BOT_TAG and replaces the three hardcoded if isPrivate bot-node blocks in GenerateWABinary.
• goneonize/version.go: align GetVersion() with the released 0.4.3.post0 (the repo was still on 0.3.13, which breaks the Python binder's version check when building from source).

NEONIZE_BOT_TAG values

Value	Behavior
on (default)	bot node in 1:1 chats — upstream behavior
off	never append the bot node

Defaults to on when unset, so this is fully backward compatible.

Notes

• Tested on Windows (amd64): on and off both verified live — the AI/bot label shows in 1:1 chats with on and is absent with off.
• Group sends with the bot node were originally considered, but WhatsApp's server rejects the node in group chats with error 479, so only on/off are exposed.
• The Go toolchain was installed fresh (go1.26.5 + WinLibs MinGW); build passes with go build -buildmode=c-shared -ldflags=-s .