chore: update project references and add Citron copyright

- Replaced all references to the old project name with Citron.
- Added Citron copyright information alongside existing notices in all files.

src/core/telemetry_session.h

@@ -92,8 +92,8 @@ u64 RegenerateTelemetryId();
 
 /**
  * Verifies the username and token.
- * @param username yuzu username to use for authentication.
- * @param token yuzu token to use for authentication.
+ * @param username citron username to use for authentication.
+ * @param token citron token to use for authentication.
  * @returns Future with bool indicating whether the verification succeeded
  */
 bool VerifyLogin(const std::string& username, const std::string& token);