chore(AI/ContextChat): update inital indexing docs

[kyteinsky]

☑️ Resolves

• Fix #…

🖼️ Screenshots

[kyteinsky]

/backport to stable31

[backportbot]

The backport to stable31 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable31
git pull origin stable31

# Create the new backport branch
git checkout -b backport/13529/stable31

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 5216a0f0

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/13529/stable31

Error: Failed to cherry pick commits: error: no cherry-pick or revert in progress
fatal: cherry-pick failed

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

[kyteinsky]

/backport a0d9a99 to stable31

[backportbot]

The backport to stable31 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable31
git pull origin stable31

# Create the new backport branch
git checkout -b backport/13529/stable31

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick a0d9a99

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/13529/stable31

Error: Failed to check for changes with origin/stable31: No changes found in backport branch

---

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