Add prompt before applying migration

[zzooeeyy]

WHY are these changes introduced?

Fixes #0000

WHAT is this pull request doing?

How to test your changes?

Post-release steps

Measuring impact

How do we know this change was effective? Please choose one:

• n/a - this doesn't need measurement, e.g. a linting rule or a bug-fix
• Existing analytics will cater for this addition
• PR includes analytics changes to measure impact

Checklist

• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've considered possible documentation changes

[zzooeeyy]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• Prevent deploy with 'scopes' #5391
• Add prompt before applying migration #5390 👈 (View in Graphite)
• Migrate scopes to required_scopes #5389
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[github-actions]

Differences in type declarations

We detected differences in the type declarations generated by Typescript for this branch compared to the baseline ('main' branch). Please, review them to ensure they are backward-compatible. Here are some important things to keep in mind:

• Some seemingly private modules might be re-exported through public modules.
• If the branch is behind main you might see odd diffs, rebase main into this branch.

New type declarations

We found no new type declarations in this PR

Existing type declarations

packages/cli-kit/dist/public/node/themes/api.d.ts

@@ -5,7 +5,7 @@ export type ThemeParams = Partial<Pick<Theme, 'name' | 'role' | 'processing' | '
 export type AssetParams = Pick<ThemeAsset, 'key'> & Partial<Pick<ThemeAsset, 'value' | 'attachment'>>;
 export declare function fetchTheme(id: number, session: AdminSession): Promise<Theme | undefined>;
 export declare function fetchThemes(session: AdminSession): Promise<Theme[]>;
-export declare function themeCreate(params: ThemeParams, session: AdminSession): Promise<Theme | undefined>;
+export declare function createTheme(params: ThemeParams, session: AdminSession): Promise<Theme | undefined>;
 export declare function fetchThemeAssets(id: number, filenames: Key[], session: AdminSession): Promise<ThemeAsset[]>;
 export declare function deleteThemeAssets(id: number, filenames: Key[], session: AdminSession): Promise<Result[]>;
 export declare function bulkUploadThemeAssets(id: number, assets: AssetParams[], session: AdminSession): Promise<Result[]>;