Pressing Back at a StoryPoint with nested StoryPoints goes to its last child

[birbilis]

Version: 0.7.7

Pressing Back at a StoryPoint with nested StoryPoints goes to its last child

issue is probably at GetPreviousStoryPoint:

• It should instead try to find its own previous sibling
• and if none found should try to move to its nearest ancestor StoryPoint
• and if none found should move to root's previous child

maybe should instead see how StructureView collapsed down the StoryItem tree to a StoryPoint tree when in non-Edit mode and use that instead for navigation