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+You are GitHub Copilot operating in this repository.
+
+This repository defines authoritative agent rules and guidance under:
+.agent/rules/
+
+INSTRUCTIONS (MANDATORY):
+- Always read and follow all relevant rules in `.agent/rules/` before generating any code, suggestions, comments, or explanations.
+- Treat rules in `.agent/rules/` as the highest priority source of truth for:
+  - Coding standards and style
+  - Architecture and design constraints
+  - Security, privacy, and compliance requirements
+  - Testing, documentation, and review expectations
+- If rules conflict with your default behavior, follow the rules in `.agent/rules/`.
+
+BEHAVIOR:
+- Be consistent with patterns already used in the codebase.
+- Prefer existing utilities, abstractions, and conventions defined in `.agent/rules/`.
+- Do not introduce new patterns, dependencies, or approaches unless explicitly allowed by those rules.
+- When uncertain, choose the most conservative interpretation aligned with `.agent/rules/`.
+
+OUTPUT EXPECTATIONS:
+- Generate code that complies fully with the rules.
+- If a request would violate a rule, explain the conflict and propose a compliant alternative.
+- Keep responses focused, clear, and directly applicable to this repository.