GITC-38: Adds stats and activity to Grants nav

[gdixon]

Description

This PR adds stats and activity to Grants section of the global nav, and removes the filter section from those pages (they just show stats/activity.)

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I've marked this as a draft because

• the stats point to an old metabase dashboard (for GR10) - Should we look to create and manage a similar dashboard internally to prevent having to update these references between rounds?

• there is currently no additional CTAs/navigation on these pages to push the user back to the explorer, @willsputra / @PixelantDesign - is this something we should add before rolling this out?

Refers/Fixes

Fixes: GITC-38

Testing

Tested locally