Add RPC badge to fallback strategy in all pages

[MatiasOS]

Description

Add the RPC indicator badge for the fallback strategy that displays a success ratio (e.g., 1/2 means the second provider succeeded) with hover details showing the provider's attempt history.

Related Issue

Closes #140

Merge openscan-explorer/network-connectors#13 before

Type of Change

• Bug fix
• New feature
• Documentation update
• Refactoring
• Performance improvement
• Other (please describe):

Changes Made

• Update RPCMetadata type to accept "fallback" strategy
• Modify the RPCIndicator component to handle fallback mode display
• Show attempt ratio (1/N) for fallback vs success count (✓ N/M) for parallel
• Add "Succeeded on attempt #N" info banner when multiple attempts are needed
• Display response time for each provider attempt
• Disable provider selection in fallback mode (informational only)
• Add fallback-specific CSS styles
• Update mergeMetadata utility to handle fallback strategy

Screenshots (if applicable)

Network page

### Blocks page

Block page

Checklist

• I have run npm run format:fix and npm run lint:fix
• I have run npm run typecheck with no errors
• I have run tests with npm run test:run
• I have tested my changes locally
• I have updated documentation if needed
• My code follows the project's architecture patterns

Additional Notes

Requires @openscan/network-connectors package update to return metadata from fallback strategy.

[github-actions]

🚀 Preview: https://pr-155--openscan.netlify.app
📝 Commit: 528ed18a150f29bf123782103aec8e4e6c17673f