Add install count warning for safer deploys

[alfonso-noriega]

🚨 NOTE: Do not merge before PR#532386 is deployed 🚨

What

Surfaces the number of affected app installations in the app deploy / app release confirmation prompt when a release removes extensions. This gives developers a clear picture of the blast radius before they confirm a destructive operation.

?  Release a new version of adaptive-vertical-app-prod?

   Extensions:
   - yo (uid: 5aab8bdc-...) (removed)

   WARNING
   This release removes extensions and related data from 1 243 app installations.
   Use caution as this may include production data on live stores.

   Type adaptive-vertical-app-prod to confirm, or press Escape to cancel.
>  █

Closes https://github.com/shop/issues-develop/issues/22421

How

New GraphQL query (app-install-count.graphql) — queries installCount on the App type, exposed by the Management API in shop/world#532386.

New appInstallCount() method on DeveloperPlatformClient + AppManagementClient implementation. PartnersClient stubs it as unsupported.

Fetched lazily in ensureDeploymentIdsPresence() — only when the extension breakdown contains removals (onlyRemote.length > 0), right before the confirmation prompt. Wrapped in try/catch so a failure never blocks the deploy.

Warning rendered in deploy-release.ts — added to the dangerous confirmation prompt (the one requiring the user to type the app name) when hasDeletedExtensions && installCount > 0.

Behaviour unchanged in these paths

• Non-interactive (--no-interactive / piped input) — prompt is skipped entirely
• --force / --allow-deletes — prompt is skipped entirely
• API call failure — warning is silently omitted, deploy proceeds normally

[alfonso-noriega]

• Add install count warning for safer deploys #7087 👈 (View in Graphite)
• main

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

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟢	Statements	82.13%	14935/18184
🟡	Branches	74.51%	7378/9902
🟢	Functions	81.25%	3779/4651
🟢	Lines	82.51%	14119/17111

Test suite run success

3933 tests passing in 1514 suites.

Report generated by 🧪jest coverage report action from 0a8f305

[github-actions]

We detected some changes at packages/*/src and there are no updates in the .changeset.
If the changes are user-facing, run pnpm changeset add to track your changes and include them in the next release CHANGELOG.

Caution

DO NOT create changesets for features which you do not wish to be included in the public changelog of the next CLI release.

[dmerand]

Found a few things worth considering