Annotation Error Handling Levels

[anthony-chaudhary]

We need more clear error handling components and framing for the various panels and levels of file loading. Generally what I am picturing is three "unavoidable" levels

• Parent file level
• Panel/Child file level
• Media specific level

With the assumption that the errors should be handled in that hierarchal order.

• e.g. A child panel should not care about other child file errors
• An error that's at the child file level should not be handled by a media specific UI
• A media specific error should not be handled by the child file

Goals are

• Clarifying where errors get added in the higher level component vs per-panel errors etc.
• Organizing the error components better, e.g having a single error component for all "top level" errors at each level

Current state, for example this was duplicated on the lower level component

    <div v-else-if="interface_type === 'compound' && annotation_ui_context.working_file_list.length === 0 && !initializing" >
      <empty_file_editor_placeholder
        :message="'Try adding child files to this compound file.'"
        :title="'This compound file has no child files.'" />
    </div>

https://github.com/diffgram/diffgram/commit/07b05bd3036b98f401ebac35b878b5433ba7a9f8