fix: Rebrand project from PiPedal to OP-Pedal

Updated branding across the project:
- CMakeLists.txt: project name, description, homepage, display version
- src/PiPedalVersion.cpp: server name string
- debian/control: package name, source, homepage, description
- vite/package.json: package name
- vite/index.html: title, meta description
- vite/public/manifest.json: name, short_name, description, URLs
- UI files: AboutDialog, AppThemed, MainPage, SettingsDialog,
  UpdateDialog, WifiConfigDialog, WifiConfigSettings,
  WifiDirectConfigSettings, Tone3000Downloader, Tone3000HelpDialog,
  WindowScale

Preserved upstream copyright/attribution and legal references.

vite/package.json

@@ -1,5 +1,5 @@
 {
-  "name": "pipedal",
+  "name": "op-pedal",
   "private": true,
   "version": "0.0.0",
   "type": "module",