Update dev.md to demonstrate custom_agent and custom_instructions with expression rendering

[Copilot]

Enhances the dev.md workflow to showcase the new assign_to_agent API options added in the PR: custom_agent and custom_instructions with GitHub expression support.

Changes

• Workflow purpose: Changed from listing issues to finding and assigning documentation candidates to the technical doc writer agent
• Safe outputs: Added assign-to-agent with max: 1
• Custom agent: Demonstrates custom_agent="technical-doc-writer"
• Expression rendering: Shows custom_instructions with expressions:

  custom_instructions="Read the description carefully. This assignment was made by @${{ github.actor }} in run ${{ github.run_id }}."

Expressions like ${{ github.actor }} are converted to environment variables in the lock file and substituted at runtime via envsubst.

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[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• https://api.github.com/user
  • Triggering command: /usr/bin/gh gh api user --jq .login (http block)
  • Triggering command: /usr/bin/gh gh api user --jq .login -json GO111MODULE ache/go/1.25.0/x64/pkg/tool/linux_amd64/vet GOINSECURE GOMOD GOMODCACHE ache/go/1.25.0/x64/pkg/tool/linu--jq env /ref/tags/v8 GO111MODULE 1/x64/bin/node GOINSECURE GOMOD GOMODCACHE /opt/hostedtoolc--jq (http block)
  • Triggering command: /usr/bin/gh gh api user --jq .login se 7721908/b219/vet.cfg 615e07f78433a71bf3835e7d37489279444/log.json GOINSECURE GOMOD GOMODCACHE /opt/hostedtoolctest-mcp-3 -V=f�� oad-artifact.git--verbose GOPROXY ache/go/1.25.0/xREDACTED GOSUMDB GOWORK -d/gh-aw ache/go/1.25.0/x-address (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)