[WIP] Investigate firewall mounting issues affecting make build command

[Copilot]

• Analyze workflow run https://github.com/githubnext/gh-aw/actions/runs/21269170295
• Understand the issue: When sandbox: false is set, the --add-dir flags do not include ${GITHUB_WORKSPACE}
• Identify root cause: Line 55-57 in copilot_engine_execution.go only adds /tmp/ paths but not the workspace directory in non-sandbox mode
• Fix: Add workspace directory to --add-dir in non-sandbox mode as well
• Add test to verify workspace directory is included in both modes
• Run tests to validate fix
• Run make agent-finish for validation

Original prompt

investigate how we can relax firewall mounting so that this run https://github.com/githubnext/gh-aw/actions/runs/21269170295 would not report difficulties of running make build command

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