Add subscription plan change guide (#647)

* Update support/subscription/changing-plan.mdx

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* Update zh-CN/support/subscription/changing-plan.mdx

Co-Authored-By: mintlify[bot] <109931778+mintlify[bot]@users.noreply.github.com>

* Update docs.json

Co-Authored-By: mintlify[bot] <109931778+mintlify[bot]@users.noreply.github.com>

* Update docs.json

Co-Authored-By: mintlify[bot] <109931778+mintlify[bot]@users.noreply.github.com>

---------

Co-authored-by: mintlify[bot] <109931778+mintlify[bot]@users.noreply.github.com>

Author: mintlify[bot]

docs.json

@@ -618,6 +618,7 @@
                     "pages": [
                       "support/subscription/subscribing",
                       "support/subscription/managing",
+                      "support/subscription/changing-plan",
                       "support/subscription/canceling"
                     ]
                   },
@@ -1266,6 +1267,7 @@
                     "pages": [
                       "zh-CN/support/subscription/subscribing",
                       "zh-CN/support/subscription/managing",
+                      "zh-CN/support/subscription/changing-plan",
                       "zh-CN/support/subscription/canceling"
                     ]
                   },

support/subscription/changing-plan.mdx

@@ -0,0 +1,49 @@
+---
+title: Changing your subscription plan
+sidebarTitle: Change subscription plan
+description: Learn how to change your Comfy Cloud subscription plan
+---
+
+## How to change your subscription plan
+
+You can upgrade or downgrade your Comfy Cloud subscription plan at any time. Follow these steps to change your plan:
+
+### Step 1: Open the settings panel
+
+Click the **Plan & Credits** menu to open the settings panel.
+
+<img src="/images/support/payment/billing-1-account.png" alt="Plan & Credits menu" />
+
+### Step 2: Access subscription management
+
+In the **Plan & Credits** panel, click the **Manage subscription** button to open the subscription settings.
+
+<img src="/images/support/subscription/subscription.jpg" alt="Manage subscription button" />
+
+### Step 3: Select a new plan
+
+Select any plan you want, then click the **Change** button.
+
+<img src="/images/support/subscription/subscribe.jpg" alt="Select subscription plan" />
+
+### Step 4: Open the billing portal
+
+After opening the Comfy billing portal, click the **Update subscription** button.
+
+<img src="/images/support/payment/comfyui-billing-portal.jpg" alt="Comfy billing portal" />
+
+### Step 5: Confirm your new plan
+
+Select the plan you want, then click **Continue** to confirm your selection.
+
+<img src="/images/support/subscription/subscription-change-plan.jpg" alt="Confirm subscription change" />
+
+## Billing for plan changes
+
+### Upgrading to a higher-priced plan
+
+If your current subscription plan price is lower than the target plan, you will need to pay the price difference. You will receive an equivalent credit amount corresponding to the price difference.
+
+### Downgrading to a lower-priced plan
+
+If your current subscription plan price is higher than the target plan, your subscription will switch to the new plan after the current billing cycle ends. The new subscription will be based on the new pricing plan.

zh-CN/support/subscription/changing-plan.mdx

@@ -0,0 +1,49 @@
+---
+title: 更改订阅计划
+sidebarTitle: 更改订阅计划
+description: 了解如何更改您的 Comfy Cloud 订阅计划
+---
+
+## 如何更改订阅计划
+
+您可以随时升级或降级您的 Comfy Cloud 订阅计划。按照以下步骤更改您的计划：
+
+### 步骤 1：打开设置面板
+
+点击 **Plan & Credits**（计划与积分）菜单，打开设置面板。
+
+<img src="/images/support/payment/billing-1-account.png" alt="计划与积分菜单" />
+
+### 步骤 2：访问订阅管理
+
+在 **Plan & Credits**（计划与积分）面板中，点击 **Manage subscription**（管理订阅）按钮，打开订阅设置。
+
+<img src="/images/support/subscription/subscription.jpg" alt="管理订阅按钮" />
+
+### 步骤 3：选择新计划
+
+选择您想要的任意计划，然后点击 **Change**（更改）按钮。
+
+<img src="/images/support/subscription/subscribe.jpg" alt="选择订阅计划" />
+
+### 步骤 4：打开账单门户
+
+打开 Comfy 账单门户后，点击 **Update subscription**（更新订阅）按钮。
+
+<img src="/images/support/payment/comfyui-billing-portal.jpg" alt="Comfy 账单门户" />
+
+### 步骤 5：确认新计划
+
+选择您想要的计划，然后点击 **Continue**（继续）确认您的选择。
+
+<img src="/images/support/subscription/subscription-change-plan.jpg" alt="确认订阅更改" />
+
+## 计划更改的计费说明
+
+### 升级到更高价格的计划
+
+如果您当前的订阅计划价格低于目标计划，您需要支付差价。您将获得与差价相对应的等额积分。
+
+### 降级到更低价格的计划
+
+如果您当前的订阅计划价格高于目标计划，您的订阅将在当前计费周期结束后切换到新计划。新订阅将基于新的定价计划。