Start Work UX refinement

[justinrobots]

• Split "start work" button into two: one for starting work on an issue, one for creating a branch #3808
• Invert flow for start work on an issue to pick issue first #3809
• Add integration connection button to title bar of select issue step #3832
• When no issues are returned, show an option to connect integrations #3833
• Reword placeholder input text during base branch selection step #3834
• Back button in "start work" goes to the wrong step #3836

[axosoft-ramint]

Done since all subtasks are complete

[github-actions]

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