Add "Essential Knowledge for New Nextcloud Administrators" Section to Admin Manual

Given the depth and breadth of the Admin Manual, maybe we can assemble a "quick start" section. This might cover "things longtime users of Nextcloud know and wish every new admin knew too". Ideally keep the "cheat sheet" limited in length (i.e. to a page or two - best effort). Some of covered topics may be brief write-ups while others are just links to the appropriate places in the Admin Manual.

Concept:

Create a dedicated 'Quick Start' or 'Essential Knowledge' section in the Admin Manual, ideally adjacent to the first installation/configuration chapters. This single reference would highlight the key things every new administrator should know to avoid confusion and common pitfalls.

Possible section titles:

• "Getting Started: Essential Knowledge for Admins"
• "Must-Know Basics for New Administrators"
• "Admin Essentials: Tools, Docs, and Best Practices"

Coverage ideas:

• The occ command: basic usage, system configuration listing (occ config:list system), important commands
• The config/config.php file: where it is, why it's important, typical parameters
• Community resources: Nextcloud community forum and when/how to use it
• Manuals overview: Brief intro to the three key guides (user manual, admin manual, developer manual)
• Maintenance essentials: Backups, performing updates, and handling upgrades
• Logging: Where to find logs, how to read them, what admins typically need
• Self-help and further documentation: How/where to find relevant info in the Admin Manual, tips for navigating the docs, app-level GitHub README files (and other app-level doc resources that are currently external to the main manuals), and where to go next
• Admin Overview screen: Using the Admin settings → Overview screen for system warnings/errors/status
  • Navigating warnings/errors in setup checks and how to find info in the manual
• Other common admin tasks and tips as appropriate
  • Email setup basics
  • Securing/hardening tips for new admins
  • Performance/optimization starting points

Rationale:

By aggregating these must-know topics and linking to deeper documentation, newcomers will save time, reduce learning curve frustration, and the support load will decrease. Where possible, keep things concise with brief tips plus links to full details.

Open to section title suggestions and additional topics!

Start by reviewing the Admin Manual structure around the installation and configuration chapters, then identify where a Quick Start or Essential Knowledge section would fit. Done should be a concise one- or two-page section covering the agreed essentials with links to deeper Admin Manual content and community resources.