[DOCS] Add docs on CapabilityFilter & CapabilityFactory

[sisyphusSmiling]

It's been noted a couple of times that the roles filled by Filter & Factory Manager are unclear in the current docs. We should add context and color to why they exist, what they accomplish, and uncover any potential foot guns in the use of these constructs. It should be clear to readers how to use these constructs to successfully filter out the Capabilities they do/don't want parent accounts to access on hybrid custody child accounts.

[austinkline]

One great result from this imo is some pre-deployed instances of factory/filter resources that anyone can use for the really common cases:

• Allow all filter (an app which doesn't need to put restrictions on NFTs)
• Factory manager for full NFT access (should have the NFTCollectionPublicFactory, NFTProviderAndCollectionFactory, and NFTProviderFactory configured
• Factory manager for full NFT and FT access (same as above, but with FT variants as well)

Thoughts? Having these premades that are deployed and managed by Flow would mean apps can experiment without even needing to make any of these resources themselves

[sisyphusSmiling]

I like this idea! Devs could then just list the address of the Flow-hosted Filter & Manager appropriate for their use case when linking.

Do you think there's a reason to maintain keys on those accounts at all or could we remove keys once configured?