Update Intellij docs

[novalisdenahi]

Description

• Update Intellij Marketplace links in the docs.
• Added Intellij docs to side bar and overview.

Notes for QA

• V1 and V2 changes
• IntelliJ docs contain marketplace link
• Integration overview and side bar should list Jet Brains/Intellij Plugin

Requirement checklist

• I have validated my changes on a test/local environment.
• I have tested that the code snippets I added work. (Leave unchecked if there are no new code snippets.)
• I have added my changes to the V1 and V2 documentations.
• I have checked the SNYK/Dependabot reports and applied the suggested changes.
• (Optional) I have updated outdated packages.

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Latest commit:	73ed1dc
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