feat(project-creation): Migrate project creation flow to new workflow engine endpoints

[malwilley]

(Note: do not merge until first merging #123033 - without this, team admins will be unable to create alerts for their projects)

The project creation UI, when custom options are checked, is currently using the old deprecated /rules/ endpoint. This PR updates the hooks to now use the new workflow engine /detectors/ and /workflows/ endpoints.

In addition, it also fixes some issues such as:

• Previously, when creating an alert which was sent to email and slack/discord/teams, it would create two separate alerts. It now creates a single alert with two actions.
• Priority alerts were being created with a 5 minute action interval when created from the frontend. It now uses an action interval of 0 to match the endpoint logic when default_rules is enabled.
• Custom alerts (e.g. "events in an issue are more than x in y minutes") were being created with a 5 minute action interval, which could result in some very noisy alerts. It was changed to a 24 hour action interval.

I've tested all 3 alert options (high priority, custom, none) on both the old and new project UIs, everything works as expected.

[sentry]

Bug: A race condition exists where the frontend queries for a project's detector immediately after creation without retries. Due to replication lag, this can fail and cause the project creation to be rolled back.
_{Severity: HIGH}

Suggested Fix

Introduce retry logic for the detector fetch operation. When calling fetchIssueStreamDetectorIdsForProjects or the underlying queryClient.fetchQuery, enable retries with a backoff strategy. This will make the process resilient to replication or indexing delays by allowing a short time for the detector to become available via the API.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's
not valid.

Location: static/app/components/onboarding/useCreateProjectRules.ts#L113-L121

Potential issue: After a project is successfully created, the frontend immediately
queries for its associated 'issue stream' detector using
`fetchIssueStreamDetectorIdsForProjects`. This query is configured with `retry: false`.
While the backend creates the detector synchronously, delays from database replication
or indexing can cause the detector to be temporarily unavailable via the API. If the
query fails to find the detector, an error is thrown, which triggers a rollback that
deletes the successfully created project. This race condition can lead to intermittent
failures in the project creation workflow.

_{Did we get this right? 👍 / 👎 to inform future reviews.}