Agent skips $HOME/.copilot/ when searching for MCP/env config files

### Describe the bug

When asked to locate a file like ado-mcp.env, the agent searched only the repo directory and then escalated to a drive-root scan
— skipping $HOME/.copilot/ entirely, despite the documentation explicitly listing it as a profile-level config directory.

The agent should apply file-type reasoning first (.env + ado-mcp prefix → MCP config → ~/.copilot/), check the documented lookup
order (repo → repo root → $HOME/.copilot/), and only ask the user if all three fail — never scan from drive root.

This is a tool-first, reasoning-last anti-pattern that should be corrected in the agent's lookup heuristics.

[bug-conversation.txt](https://github.com/user-attachments/files/26563816/bug-conversation.txt)

### Affected version

GitHub Copilot CLI 1.0.21.

### Steps to reproduce the behavior

1. save ado mcp details in ~/.copilot/ado-mcp.env
2. go to your repo folder
3. ask: create pull request

### Expected behavior

it should have look into ~/.copilot folder for env file

### Additional context

Operating system: windows 11
processor : x86_64
terminal: windows terminal
bash: git bash

Start by reproducing the lookup from a repository on Windows 11 with ~/.copilot/ado-mcp.env present, and review the attached bug-conversation.txt alongside the documented lookup order. Done means the agent checks the repository, repository root, and $HOME/.copilot/ before asking the user, without escalating to a drive-root scan.

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