Feat polish changes

[imsergiy]

• highlight the page we are on
• show correct flow on diagram
• fix hidden examples on PDF search
• add link to hub in header
• fix spacing issues
• default to PDF search
• remove confusing file limit

[netlify[bot]]

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[github-actions[bot]]

:tada: This PR is included in version 0.5.0 :tada:

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot :package::rocket: