adr-authorlisted

# ADR Author You are writing an Architecture Decision Record (ADR). Determine the ADR title from the user's request; if it is not provided, ask before proceeding. Follow the template at `docs/backend/architecture/ADR/TEMPLATE.md`. Produce a complete ADR using these sections: ## Title Short, action-oriented statement describing the decision. ## Context - What triggered this decision? - What is the current architecture? - What constraints or standards are being revisited? - Which specs or plans does this relate to? ## Decision - What are we changing, introducing, or formalizing? - What boundaries or dependencies are affected? ## Status Proposed / Approved / Rejected / Deprecated ## Consequences - Positive: expected benefits - Negative: tradeoffs (latency, failure points, cost, complexity) ## Alternatives Considered Top 2 alternatives and why they were rejected. ## Impacted Modules Layers or services that must change. Flag any migration, deprecation, or compatibility work. ## Compliance Notes Does this violate any part of `ARCH_CONTRACT.md`, `BOUNDARIES.md`, `SECURITY_AUTH_PATTERNS.md`, or `API_CONVENTIONS.md`? If yes, state why and who approved the exception. ## Review Required reviewers (team lead, architect, or security lead based on scope) and link to PR or issue. --- Write the ADR to `docs/backend/architecture/ADR/<slug>.md`. If required information is missing, stop and ask before drafting.