Scan: Implemented validator index top part and uptimechart

[pzshine]

Fixed: #2433
Fixed: #2436

Implementation details

• Implemented a top part for the validator index page
• Implemented Uptime Chart on the validator index page
• Improved the CTooltip component to be more powerful.

Note:

• Now, oracle reports and rank are mock data.

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[render]

Your Render PR Server URL is https://d3n-scan-pr-2497.onrender.com.

Follow its progress at https://dashboard.render.com/static/srv-bsufn58ti7jbdtbegfog.

[evilpeach]

1. Let's disable this link
   
2. Please fix it on 320px
   

[evilpeach]

LGTM