Add support for all agents in custom instructions in JetBrains section

[ChihweiLHBird]

Why:

@Eskibear from the Copilot team confirms AGENTS.md support in JetBrains plugin has been implemented.

Closing this as it's already supported.

microsoft/copilot-intellij-feedback#598 (comment)

What's being changed (if available, include any code snippets, screenshots, or gifs):

Showing agent instructions files like AGENTS.md and CLAUDE.md as supported on this page.

Check off the following:

• A subject matter expert (SME) has reviewed the technical accuracy of the content in this PR. In most cases, the author can be the SME. Open source contributions may require an SME review from GitHub staff.
• The changes in this PR meet the docs fundamentals that are required for all content.
• All CI checks are passing and the changes look good in the review environment.

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.

[github-actions]

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Table of review links

Note: Please update the URL for your staging server or codespace.

The table shows the files in the content directory that were changed in this pull request. This helps you review your changes on a staging server. Changes to the data directory are not included in this table.

Source	Review	Production	What Changed
copilot/reference/custom-instructions-support.md	fpt ghec	fpt ghec

Key: fpt: Free, Pro, Team; ghec: GitHub Enterprise Cloud; ghes: GitHub Enterprise Server

🤖 This comment is automatically generated.

[Sharra-writes]

@ChihweiLHBird I will check with the Copilot team and make sure this is something we want documented. In the future, written context that isn't a link to a very long comment thread would be helpful. We do occasionally reject PRs on the "too hard to figure out what's going on here" principle, and asking writers to wade through a long thread of technical comments is a lot.

[ChihweiLHBird]

@Sharra-writes thanks for the feedback! I updated the PR description with a quote from the Copilot team member.

[nickzhums]

Hi this is nick from the product team. Looking at this page, it says "custom instructions", this is a different file than "Agents.md" support in the original issue. I don't know if this is the right page, is there a specific page for Agents.md support?