Create Start-FabricNotebook cmdlet #194

Inspired by Kevin Chant showing his PowerShell code to start a notebook (during SQLBits 2026).

The function should invoke a given notebook (by name or id) and (by default) wait for completion.

Behavior

• Require WorkspaceId and exactly one of NotebookId or NotebookName.
• Wait for completion by default. Allow callers to opt out and return the submitted job instance promptly.
• When waiting, poll until the job reaches a terminal state, honoring the API's Retry-After header. Return the final job status and surface failure details when execution fails.
• Support -WhatIf so callers can preview the operation without starting the notebook.

Implementation details

• Resolve notebook names within the specified workspace; report not-found and ambiguous-name cases instead of selecting an arbitrary notebook.
• Submit a RunNotebook job through the Fabric Job Scheduler API.
• Poll the job-instance URL returned by the submit response. This is a job-instance workflow, not the generic long-running-operation flow that polls using x-ms-operation-id.
• Defer notebook parameters and compute/environment configuration from the initial implementation unless they are needed for the core use case.