feat: generate chain config during block-explorer initialization

[artemijspavlovs]

PR Standards

Opening a pull request should be able to meet the following requirements

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For Author:

• Targeted PR against correct branch
• Included the correct type prefix in the PR title
• Linked to Github issue with discussion and accepted design
• Targets only one github issue
• Wrote unit and integration tests
• All CI checks have passed
• Added relevant godoc comments

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For Reviewer:

• Confirmed the correct type prefix in the PR title
• Reviewers assigned
• Confirmed all author checklist items have been addressed

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After reviewer approval:

• In case PR targets main branch, PR should be squashed and merged.
• In case PR targets a release branch, PR should be rebased.