Empty state for work items planning view page

What does this MR do and why?

Fix empty state for work items planning view page

References

Relates to #578377 (closed)

Screenshots or screen recordings

Recording	Scenerio
Screen_Recording_2025-11-24_at_4.42.54_PM	Project Level
	Group Level (No Projects exist && using Free version)
Screen_Recording_2025-11-24_at_4.41.09_PM	Group Level (Projects exist && using Free version)
Screen_Recording_2025-11-24_at_4.44.10_PM	Group Level (Premium + version – doesn't matter if projects exist or not)

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Related to #578377 (closed)