chore(harness): make repository agent-ready

Add concise routed context, task-aware agent roles, focused skills, and structured learning promotion.\n\nUnify local development and workspace tooling, add layered test and E2E verification, harden MCP authentication, and gate deployment behind verification and explicit production promotion.

docs/product/redemption.md

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+# Redemption codes
+
+Promotional codes are redeemed only through `apps/web/app/redeem/page.tsx`.
+Do not add redemption UI or a redemption call to the mobile app: mobile premium
+access is governed by the platform purchase/RevenueCat flow.
+
+The public web form calls `redeem-code`, which delegates the atomic validation and
+grant to `redeem_code_by_email`. The database boundary validates active state,
+expiry, remaining uses, and prior redemption before changing premium status.
+
+Changes require web E2E coverage for validation and success/error states plus a
+Supabase integration assertion for the resulting profile and redemption record.