feat(deco-ai-gateway): move billing defaults to database config table

[JonasJesus42]

Create llm_gateway_config singleton table to store configurable billing defaults (prepaid/postpaid limits, hard cap, markup %, min Stripe amount). Replace hardcoded constants with async loadGatewayDefaults() that reads from DB with 5-min cache and falls back to previous hardcoded values.

Made-with: Cursor

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Summary by cubic

Moves billing defaults to a DB-backed config so limits, hard cap, markup, and minimum Stripe charge can be changed without deploys. Also removes a duplicate llm_gateway_config schema definition.

• New Features

  • Added llm_gateway_config singleton table (prepaid/postpaid limits, hard cap, markup %, min Stripe amount) with service_role RLS.
  • Implemented getGatewayDefaults (5‑min cache) and wired it into provisioning, credits, set-limit, and saveApiKey.

• Migration

  • Run the schema migration to create llm_gateway_config and its policy (inserts the 'global' row).
  • Optionally set custom values in llm_gateway_config; defaults mirror previous hardcoded values.

^{Written for commit f6ff84e. Summary will update on new commits.}

[github-actions]

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[cubic-dev-ai]

1 issue found across 8 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="deco-ai-gateway/server/db/schema.sql">

<violation number="1" location="deco-ai-gateway/server/db/schema.sql:44">
P2: This introduces a duplicated schema/policy definition for `llm_gateway_config` in the same script. Keep a single source of truth to avoid drift when defaults or policy rules change.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}