Add error handling to top-level pages

[ohltyler]

Description

This PR improves error handling a few different ways:

• bubbles up persisted errors as toast notifications at the top-level workflows page and workflow_detail page
• filters out unnecessary backend errors and hide on the frontend when appropriate. currently, this just means not showing an index_not_found_exception when executing the search workflows API so we don't show errors on a fresh cluster when loading any of the pages, for example

Testing

• ensured index_not_found_exception is hidden appropriately
• ensured toasts show for create, save, update, delete workflow failures on the base pages
• ensured there is no multiple / re-rendering of the toasts (not triggering several toasts for the same error)

Misc

• improved save state. updating the form only on change for text_field to prevent clicking on the form, and clicking away to automatically set the page to dirty, even if no underlying values were changed
• improved loading state if rendering a page for a workflow ID that is not found

Check List

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