* feat: support year/month subscription
* feat: add GetPrice() for plan
* feat: add GetDuration
* feat: gofumpt
* feat: add subscription mode for pricing
* feat: restrict auto create product operation
* fix: format code
* feat: add period for plan,remove period from pricing
* feat: format code
* feat: remove space
* feat: remove period in signup page
* feat: fix price display
* feat: support subscription
* feat: fix select-plan-> signup -> buy-plan -> login flow
* feat: support paid-user to login and jump to the pricing page
* feat: support more subscription state
* feat: add payment providers for plan
* feat: format code
* feat: gofumpt
* feat: redirect to buy-plan-result page when user have pending subscription
* feat: response err when pricing don't exit
* Update PricingListPage.js
* Update ProductBuyPage.js
* Update LoginPage.js
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Co-authored-by: hsluoyz <hsluoyz@qq.com>