Add v13 global DB overview dashboard

[avandras]

Description

Reworked dashboard for Grafana v13

AI & Automation Policy

• I am the human author and take full personal responsibility for every change in this PR.
• No AI or automated generative tool was used in any part of this PR OR I have disclosed all tool(s) below.

AI/automation tools used (leave blank if none):

Checklist

• Code compiles and existing tests pass locally.
• New or updated tests are included where applicable.
• Documentation is updated where applicable.

[coveralls]

Coverage Report for CI Build 28237957066

Coverage decreased (-0.1%) to 85.746%

Details

• Coverage decreased (-0.1%) from the base build.
• Patch coverage: No coverable lines changed in this PR.
• 8 coverage regressions across 1 file.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

8 previously-covered lines in 1 file lost coverage.

File	Lines Losing Coverage	Coverage
internal/sinks/prometheus.go	8	93.95%

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Coverage Stats

Relevant Lines:	5451
Covered Lines:	4674
Line Coverage:	85.75%
Coverage Strength:	0.98 hits per line

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💛 - Coveralls