Docs: add Calcite settings examples #4806

[AzazelSensei]

Description

I added curl examples for the Calcite plugin settings and fixed the v3 engine and join doc links in that section.

Related Issues

Resolves #4806

Check List

• New functionality includes testing.
• New functionality has been documented.
• New functionality has javadoc added.
• New functionality has a user manual doc added.
• New PPL command checklist all confirmed.
• API changes companion pull request created.
• Commits are signed per the DCO using --signoff or -s.
• Public documentation issue/PR created.

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[github-actions]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

🧪 No relevant tests

🔒 No security concerns identified

✅ No TODO sections

🔀 No multiple PR themes

⚡ Recommended focus areas for review Broken Link The link ../../dev/intro-v3-engine.md uses a relative path that likely does not resolve correctly from the current file location. The old path was ../../../dev/intro-v3-engine.md (three levels up), but the new path only goes two levels up. This will result in a 404 error when users click the link. Check `introduce v3 engine <../../dev/intro-v3-engine.md>`_ for more details. Wrong Extension The link ../ppl/cmd/join.md references a .md file, but the old link used .rst extension. If the documentation system uses reStructuredText (.rst) files, this link will be broken. The file extension should match the actual file type in the repository. Check `join doc <../ppl/cmd/join.md>`_ for example.

[github-actions]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
General	Fix incorrect file extension reference The file extension for the v3 engine link should be .rst instead of .md to maintain consistency with reStructuredText documentation format. This ensures proper link resolution in the documentation build system. docs/user/admin/settings.rst [1027-1028] -Check `introduce v3 engine <../../dev/intro-v3-engine.md>`_ for more details. +Check `introduce v3 engine <../../dev/intro-v3-engine.rst>`_ for more details. Check `join doc <../ppl/cmd/join.md>`_ for example. Suggestion importance[1-10]: 7 __ Why: The suggestion correctly identifies that the link to intro-v3-engine.md should use .rst extension for consistency with reStructuredText documentation. However, the PR shows the path was changed from ../../../dev/intro-v3-engine.md to ../../dev/intro-v3-engine.md, and the suggestion addresses the file extension issue which could cause broken links if the actual file uses .rst extension.	Medium