docs: normalize legacy server product name to "ownCloud Classic"

Rename the legacy server product to "ownCloud Classic" in the README
prose, applying the version only as additional information where
relevant ("ownCloud Classic 10"). URLs, the oCIS reference, and all
other identifiers are left untouched.

Part of the cross-repo rebrand tracked in owncloud/docs#5111.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Signed-off-by: Thomas Müller <1005065+DeepDiver1975@users.noreply.github.com>

Author: DeepDiver1975

README.md

@@ -4,17 +4,17 @@
 
 [![License](https://img.shields.io/badge/License-AGPL--3.0-blue.svg)](COPYING) [![ownCloud OSPO](https://img.shields.io/badge/OSPO-ownCloud-blue)](https://kiteworks.com/opensource) [![Docker Hub](https://img.shields.io/docker/pulls/owncloud)](https://hub.docker.com/r/owncloud/server)
 
-ownCloud Core is the server-side component of ownCloud 10 (Classic), providing file storage, synchronization, and sharing trusted by over 200 million users worldwide. It includes WebDAV, CalDAV, and CardDAV servers, a plugin architecture for apps, user and group management, encryption support, external storage backends, and a comprehensive REST API. The server runs on PHP with support for MySQL, MariaDB, PostgreSQL, and SQLite databases.
+ownCloud Core is the server-side component of ownCloud Classic 10, providing file storage, synchronization, and sharing trusted by over 200 million users worldwide. It includes WebDAV, CalDAV, and CardDAV servers, a plugin architecture for apps, user and group management, encryption support, external storage backends, and a comprehensive REST API. The server runs on PHP with support for MySQL, MariaDB, PostgreSQL, and SQLite databases.
 
-## Part of Classic (OC10)
+## Part of ownCloud Classic
 
-This is the main repository for [ownCloud Server (Classic)](https://github.com/owncloud/core), also known as ownCloud 10 or OC10. It is the foundation that apps like [Activity](https://github.com/owncloud/activity), [Calendar](https://github.com/owncloud/calendar), [Contacts](https://github.com/owncloud/contacts), and many others extend. The server is available as a Docker image on [Docker Hub](https://hub.docker.com/r/owncloud/server).
+This is the main repository for [ownCloud Classic](https://github.com/owncloud/core), also known as ownCloud Classic 10. It is the foundation that apps like [Activity](https://github.com/owncloud/activity), [Calendar](https://github.com/owncloud/calendar), [Contacts](https://github.com/owncloud/contacts), and many others extend. The server is available as a Docker image on [Docker Hub](https://hub.docker.com/r/owncloud/server).
 
 For the next-generation ownCloud platform, see [ownCloud Infinite Scale (oCIS)](https://github.com/owncloud/ocis).
 
 ## Getting Started
 
-For installing ownCloud Server, see the official [ownCloud 10 installation manual](https://doc.owncloud.com/server/latest/admin_manual/installation/).
+For installing ownCloud Classic, see the official [ownCloud Classic 10 installation manual](https://doc.owncloud.com/server/latest/admin_manual/installation/).
 
 ### Development Build Prerequisites
 
@@ -27,7 +27,7 @@ make
 
 ## Documentation
 
-- [ownCloud Server documentation](https://doc.owncloud.com)
+- [ownCloud Classic documentation](https://doc.owncloud.com)
 - [Developer documentation](https://doc.owncloud.com/server/latest/developer_manual/)
 - [CHANGELOG.md](https://github.com/owncloud/core/blob/master/CHANGELOG.md)
 - [Conventional Commits specification](https://www.conventionalcommits.org/)