v1.16.1 — Real TheNerdyBox branding in the Windows installer

Installer-only patch: TheNerdyBox branding in the setup wizard itself, not just the app.

• Branded installer graphics — the real TheNerdyBox logo replaces NSIS's generic stock imagery throughout the wizard.
• Install path now nests under a publisher folder — C:\Program Files\TheNerdyBox\Stream Composer Suite\ instead of installing directly into Program Files' root.
• Start Menu folder now defaults to "TheNerdyBox" instead of the product name (still user-editable).
• New "Check us out on the web" checkbox on the finish page, checked by default — opens https://thenerdybox.com in your browser if still checked when you hit Finish.

Built on Tauri's own default NSIS template (pulled from the exact tauri-cli v2.11.4 tag this project uses, not guessed), with only the install-path logic and finish page modified. The finish-page checkbox reuses the same nsDialogs technique this installer's uninstaller page already used for its own custom checkbox — NSIS only ships two built-in finish-page checkbox slots, and both were already taken (Launch app, Create desktop shortcut).

Compiles clean with no warnings on the new bitmap assets. One thing that genuinely needs your own eyes: the exact on-screen placement of the new checkbox relative to the existing ones — see Tests/v1.16.1-installer-branding/WHAT_TO_TEST.md in the repo for the full checklist.