Update documentation

[fiexer]

• Update dApp staking page for developers: delete form, insert link to SpaceLabs
• Delete Ecosystem -> Community page: outdated and need regular updates
• Improve Ecosystem -> Initiatives page: add more information about SpaceLabs, add Astar Degens in the list
• Update Ledger wallet page -> changed layout
• Add 3rd part of Hoon's vision to the XCM page

[github-actions]

Visit the preview URL for this PR (updated for commit d2892b1):

https://astar-docs--pr37-doc-update-july-dr4jkp4q.web.app

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[Kahonnohak]

Hi I don't have any objection to this PR of course (approved) - but sorry to moan, I still think those About Astar and Ecosystem should be in the front.

People usually think those 1,2,3 are the same - otherwise, you would believe the front where you would land. However currently front has less content than the doc actually has. In some cases, UI design limits contents on mobile as it doesn't have space etc but for this case, we look like we are hiding our tokenomics from users. I hope to have 'About Astar' and 'Ecosystem' sections on the front soon. I think we only need two icons from Nate and captions for each. Unless we have reasons to hide them from the front.

[fiexer]

@Kahonnohak let me create a new PR later with the changes you requested.