Fix MD ordered list numbering to use 1. for all items in agent markdown files

[Copilot]

All ordered lists in the agent markdown files were using explicit sequential numbers (1., 2., 3., …) instead of the idiomatic 1. / 1. / 1. pattern that lets the renderer auto-increment.

Changes

• .github/agents/code-review.agent.md — 8-item review steps list
• .github/agents/Documentation.md — 4-item important rules list
• .github/agents/Security.md — 5-item critical rules list
• .github/agents/Style.md — two lists (4 + 2 items)

✅ Checklist

• Add tests (E2E, unit tests)
• Update RELEASENOTES.md
• Update documentation (e.g. for new settings or scenarios)
• Add telemetry

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