feat: show modal when switching to incompatible providers

[colocated]

What is this PR about?

This commit shows a modal after validating the form data with Zod to confirm that the user intends to switch providers after being told that the preview deployments feature will disabled, as it's only compatible with one of the available application source types.

Checklist

Before submitting this PR, please make sure that:

• You created a dedicated branch based on the canary branch.
• You have read the suggestions in the CONTRIBUTING.md file https://github.com/Dokploy/dokploy/blob/canary/CONTRIBUTING.md#pull-request
• You have tested this PR in your local instance. If you have not tested it yet, please do so before submitting. This helps avoid wasting maintainers' time reviewing code that has not been verified by you.

Issues related (if applicable)

None, new feature

Screenshots (if applicable)

Runs Zod validation checks BEFORE showing the modal to prevent confusion

Shows a modal if the change is valid to make sure the user wants to disable the preview deployments feature (only triggers if sourceType = 'github' and previewDeployments are enabled as a feature on the application)

Greptile Summary

This PR adds a confirmation modal when a user saves a non-GitHub provider (Bitbucket, GitLab, Gitea, Docker, plain Git, drag-and-drop) while the application currently has GitHub + preview deployments active. It also hides the "Preview Deployments" tab for non-GitHub source types, and consistently sets isPreviewDeploymentsActive: false on the server for every non-GitHub save mutation. The refetch → utils.application.one.invalidate change is a minor cache-management improvement bundled in.

Confidence Score: 5/5

Safe to merge — logic is correct, server-side enforcement is consistent, and no critical issues remain.

The confirmation guard fires when and only when it should (sourceType === 'github' + isPreviewDeploymentsActive). Server mutations independently set isPreviewDeploymentsActive: false for every non-GitHub provider, so correctness doesn't depend solely on the UI path. The double-validation in the confirmation path is harmless. Previous P1 concerns have been addressed or acknowledged. All remaining observations are P2 or lower.

No files require special attention.

_{Reviews (4): Last reviewed commit: "fix: use application document invalidate..." | Re-trigger Greptile}

[colocated]

@greptileai reset confidence score

[colocated]

Converting to draft as I've found a UI bug, will fix and republish

[colocated]

There was a bug when saving the docker provider (which is what i tested with) that it wouldn't properly hide the tab on a fresh project until next refresh of the page, so we use a different method to invalidate and reload the component now.

@greptileai re-review