What

Clean up desktop credits prompt behavior across budget banners, Rewards hints, and Chinese copy.

Why

This addresses the credits prompt regressions tracked in #905, #907, and #912.

How

• centralize budget-banner route policy so Home stays inline, Skills pages stay hidden, and session surfaces keep their dedicated handling
• gate the Rewards switch-back hint on BYOK + cloudBalance.totalBalance > 0
• update zh-CN budget banner terminology from 套餐额度 to 可用积分
• add regression coverage for route gating, Rewards hint behavior, and zh-CN copy

Affected areas

• Desktop app (Electron shell)
• Controller (backend / API)
• Web dashboard (React UI)
• OpenClaw runtime
• Skills
• Shared schemas / packages
• Build / CI / Tooling

Checklist

• pnpm typecheck passes
• pnpm lint passes
• pnpm test passes
• pnpm generate-types run (if API routes/schemas changed)
• No credentials or tokens in code or logs
• No any types introduced (use unknown with narrowing)

Notes for reviewers

• No API route or schema changes in this PR.
• Manual verification covered Update i18n/terminology: Replace '套餐额度' with '可用积分' in dashboard banner #905 and both Confusing prompt to switch back to official model on Rewards page when balance is 0 #912 BYOK branches, plus the Skills route behavior from Remove credits warning banner from Skills page #907.
• Per current scope, the Sessions-surface follow-up was not used as a release blocker for this PR.