fix(deco-ai-gateway): reconcile billing mode for postpaid limit updates

[JonasJesus42]

Persist limit period semantics and allow postpaid limit updates to honor explicit billing mode so legacy prepaid rows do not block limit reductions.

Made-with: Cursor

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Summary by cubic

Persisted limit reset periods and honored explicit billing mode for postpaid limit updates. Fixes legacy prepaid rows blocking limit reductions, aligns tools around limit_period, and avoids null % in usage when a limit is zero.

• Bug Fixes

  • Postpaid limit updates now respect explicit billing_mode and limit_period and allow lowering limits.
  • Replaced is_subscription checks with limit_period; kept is_subscription in sync for backwards compatibility. Avoided null percent display when limit ≤ 0.

• New Features

  • Added limit_period (daily/weekly/monthly) to the DB with auto-migration from is_subscription=true → monthly.
  • Set Limit tool supports limit_period (including "none") and optional billing_mode override; persists updates.
  • Credits and Usage tools now expose limitPeriod and percentUsed with clearer postpaid summaries.

^{Written for commit 46d6f75. Summary will update on new commits.}

[github-actions]

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[cubic-dev-ai]

1 issue found across 10 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/tools/usage.ts">

<violation number="1" location="deco-ai-gateway/server/tools/usage.ts:137">
P2: Handle non-positive limits so the summary doesn’t print `null% used` when `d.limit` is 0.</violation>
</file>

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