[Feature] AI Credits widget: "Revoke Operator" button with confirmation dialog

[goodbounties-nanoclaw-agent]

Feature summary

Add a red "Revoke Operator" button to the Manage tab's BuyerOperatorCard in packages/ai-credits-widget. Clicking it opens a confirmation dialog explaining that revoking will deduct any bonus balance and stop any active stream bonuses; confirming triggers the revoke action.

Problem or opportunity

BuyerOperatorCard.tsx (packages/ai-credits-widget/src/components/manage/) already shows operator-consent state (operatorConsented, operatorConsentPending) and a "Sign Consent"/"Consented" action, but there is no way for a user to revoke operator status once granted. Users need a clear, deliberate way to revoke, with an explicit warning about the consequences (bonus deduction, stream bonuses stopped) before they do it.

Proposed solution

1. Add a red "Revoke Operator" button to BuyerOperatorCard.tsx, shown when operatorConsented is true, using the existing Button component with the existing error/red color token (no new button variant).
2. On click, open a confirmation dialog using the existing imperative dialog system (createDialog/GoodWidgetDialog in packages/ui/src/components/Dialog.tsx) — no new dialog component.
3. Dialog copy explains: revoking removes the operator's ability to act on your behalf; any bonus balance will be deducted, and any active stream bonuses will stop.
4. On confirm, call a new revokeOperatorConsent action (to be added to widgetRuntimeContract.ts/backendClient.ts, since no revoke action currently exists in this package) which calls the antseed-integration backend's operator-reset endpoint . assume it will be on /v1/accounts/revoke-operator and it will require signature hash in similar format to other permissioned endpoints.

Required states, flows, and behaviors

• operatorConsented === true → "Revoke Operator" button visible (red).
• operatorConsented === false (no operator granted) → button not shown.
• Click "Revoke Operator" → confirmation dialog opens; no action taken yet.
• Confirm in dialog → revoke action fires; on success, card updates to reflect no operator consented (mirrors the existing "Sign Consent" success-state update).
• Cancel/dismiss dialog → no change, operator remains active.
• Revoke action failure → error surfaced consistent with existing error handling in BuyerOperatorCard.tsx.

Acceptance criteria

• "Revoke Operator" button is red and only visible when operator consent is currently active.
• Clicking it always shows a confirmation dialog before any revoke action is taken.
• Dialog copy explains bonus-balance deduction and stream-bonus stoppage.
• Confirming revokes operator status end-to-end (calls the backend reset endpoint) and updates the UI state.
• Canceling the dialog leaves operator status unchanged.
• Reuses existing Button/Dialog components and color tokens — no new UI primitives added.

Additional context

Requested by Hadar Rottenberg (Bounty Lead) in #goodbounties-lead, 2026-08-10 — standalone from issue #150 (explicit consent-step gating/copy), per Hadar's confirmation. Depends on the antseed-integration operator-reset endpoint (companion bounty, tracked separately) for the actual on-chain/backend revoke call — flag as an open dependency for the plan stage if that endpoint isn't ready yet. Relevant files: packages/ai-credits-widget/src/components/manage/BuyerOperatorCard.tsx, packages/ai-credits-widget/src/operatorConsent.ts, packages/ai-credits-widget/src/widgetRuntimeContract.ts, packages/ai-credits-widget/src/backendClient.ts, packages/ui/src/components/Dialog.tsx.

See PR GoodDollar/antseed-integration#24 with the revokeOperator endpoint

Create the plan (keep this section in the issue body)

Based on the above description create an execution plan in a new sub-issue and preserve the original issue content unchanged.
Do not execute the plan until given instructions to do so.

Sub-issue requirements:

• Title format: [DRAFT][PLAN] <what issue is being planned>
• Type: Task
• Description must start with: <sub-issue title>
• Link the sub-issue back to this parent issue.

Instructions when creating the plan:

• Map relevant files that are too be used as reference from all repos mentioned
• import existing @GoodDollar packages
• Map new components that should be created. Assess when a new component should be created in the new savings widget package or made part of the reusable packages/ui

Plan specification required sections:

• Required states, flows, and behaviors
• Execution plan
• acceptance criteria
• human-reviewer checklist