feat: add section on activity app admin configuration to include mail_max_items config

[cristianscheid]

☑️ Resolves

• Related to feat: make amount of items sent on email configurable via occ activity#2673

• related PR (link above) should be merged first as it includes a new config (mail_max_items) that can be set via occ command for the activity app
• this PR documents that this config exists, it's purporse and how to set a value for it

🖼️ Screenshots

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✅ Checklist

• I have built the documentation locally and reviewed the output
• Screenshots are included for visual changes
• I have not moved or renamed pages (or added a redirect if I did)
• I have run codespell or similar and addressed any spelling issues

[github-actions]

📖 Documentation Preview

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📄 1 changed documentation page

• admin_manual/configuration_server/activity_configuration.rst

Last updated: Thu, 25 Jun 2026 10:09:55 GMT

[AndyScherzinger]

/backport to stable34

[AndyScherzinger]

/backport to stable33

[backportbot]

The backport to stable33 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable33
git pull origin stable33

# Create the new backport branch
git checkout -b backport/15202/stable33

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 77061b7c

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/15202/stable33

Error: Failed to check for changes with origin/stable33: No changes found in backport branch

---

Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.

[AndyScherzinger]

/backport to stable33

[backportbot]

The backport to stable33 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable33
git pull origin stable33

# Create the new backport branch
git checkout -b backport/15202/stable33

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 77061b7c

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/15202/stable33

Error: Failed to check for changes with origin/stable33: No changes found in backport branch

---

Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.

[cristianscheid]

/backport to stable34