Fix documentation on location of custom agents and instructions in user data folder

[j4-c4]

• Copilot Chat Extension Version: 0.41.2
• VS Code Version: 1.113.0
• OS Version: Windows 11
• Feature (e.g. agent/edit/ask mode): Custom agents/instructions files
• Selected model (e.g. GPT 4.1, Claude 3.7 Sonnet): N/A
• Logs: N/A

Steps to Reproduce:

1. Place a custom agent in %APPDATA\Code\User\agents, or instructions in %APPDATA\Code\User\instructions as documented (agents, instructions
2. Check the agent picker for the agent - it is missing
3. Send a prompt, check logs to determine if instructions file was loaded - it was not
4. Check Chat Customisations window to see if either is visible - they are not.

Note: the pages say this about where user profile scoped agents etc. are stored:

~/.copilot/agents, agents folder of the current VS Code profile

and that page says that profiles are stored in %APPDATA%\Code\User\profiles on Windows. Currently, the only user data folder that picks up agents, instructions or prompts is %APPDATA%\Code\User\prompts (i.e. outside the profile folder), so I've assumed %APPDATA%\Code\User is the correct location for the agents/instructions folders. Putting the folders inside %APPDATA%\Code\User\profiles\<profile_id>\ still doesn't work though.

[aeschli]

The documentation is misleading (or wrong).
In the shared user folder, it is in a folder called .../User/prompts, and that is, for historical reasons, user for all chat customizations (instructions, prompts, custom agents...).

That said, the actual name of that folder in the user data folder is an internal implementation detail and really does not need to be known to the user.

[ntrogh]

Updating docs to remove misleading language. Thanks for pointing this out!