feat(server): runtime setting support (#5602)

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<details open="true"><summary>Generated summary (powered by <a href="https://app.graphite.dev">Graphite</a>)</summary>

> ## TL;DR
> This pull request adds a new migration file, a new model, and new modules related to runtime settings. It also introduces a new `Runtime` service that allows getting, setting, and updating runtime configurations.
>
> ## What changed
> - Added a new migration file `migration.sql` that creates a table called `application_settings` with columns `key` and `value`.
> - Added a new model `ApplicationSetting` with properties `key` and `value`.
> - Added a new module `RuntimeSettingModule` that exports the `Runtime` service.
> - Added a new service `Runtime` that provides methods for getting, setting, and updating runtime configurations.
> - Modified the `app.module.ts` file to import the `RuntimeSettingModule`.
> - Modified the `index.ts` file in the `fundamentals` directory to export the `Runtime` service.
> - Added a new file `def.ts` in the `runtime` directory that defines the runtime configurations and provides a default implementation.
> - Added a new file `service.ts` in the `runtime` directory that implements the `Runtime` service.
>
> ## How to test
> 1. Run the migration script to create the `application_settings` table.
> 2. Use the `Runtime` service to get, set, and update runtime configurations.
> 3. Verify that the runtime configurations are stored correctly in the database and can be retrieved and modified using the `Runtime` service.
>
> ## Why make this change
> This change introduces a new feature related to runtime settings. The `Runtime` service allows the application to dynamically manage and modify runtime configurations without requiring a restart. This provides flexibility and allows for easier customization and configuration of the application.
</details>

packages/frontend/core/src/components/affine/setting-modal/general-setting/plans/ai/actions/subscribe.tsx

@@ -52,7 +52,7 @@ export const AISubscribe = ({ ...btnProps }: AISubscribeProps) => {
         idempotencyKey,
         plan: SubscriptionPlan.AI,
         coupon: null,
-        successCallbackLink: null,
+        successCallbackLink: '/ai-upgrade-success',
       });
       popupWindow(session);
       setOpenedExternalWindow(true);

packages/frontend/core/src/components/affine/setting-modal/general-setting/plans/plan-card.tsx

@@ -263,7 +263,7 @@ const Upgrade = ({ recurring }: { recurring: SubscriptionRecurring }) => {
       idempotencyKey,
       plan: SubscriptionPlan.Pro, // Only support prod plan now.
       coupon: null,
-      successCallbackLink: null,
+      successCallbackLink: '/upgrade-success',
     });
     setMutating(false);
     setIdempotencyKey(nanoid());

packages/frontend/core/src/pages/subscribe.tsx

@@ -65,7 +65,10 @@ export const Component = () => {
                   recurring?.toLowerCase() === 'monthly'
                     ? SubscriptionRecurring.Monthly
                     : SubscriptionRecurring.Yearly,
-                successCallbackLink: null,
+                successCallbackLink:
+                  plan?.toLowerCase() === 'ai'
+                    ? '/ai-upgrade-success'
+                    : '/upgrade-success',
               });
               setMessage('Redirecting...');
               location.href = checkout;