Proposed Changes

This PR introduces a new optional feature to help detect potential data loss scenarios during RabbitMQ node startup. The feature adds a verify_initial_run configuration option that defaults to false. When enabled, nodes will create a marker file called node_initialized.marker on their first startup and use this to verify data consistency on subsequent restarts.

The implementation works by adding a new boot step called initial_run_check that runs after recovery but before the existing empty_db_check step.

If the marker file exists but database tables are empty, this indicates a potential data loss scenario such as corruption, accidental database resets, or split-brain recovery issues. In these cases, the node will fail to start with a specific error cluster_already_initialized_but_tables_empty, giving operators clear indication that manual intervention may be required rather than silently starting with empty data.

Types of Changes

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• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
• Documentation improvements (corrections, new content, etc)
• Cosmetic change (whitespace, formatting, etc)
• Build system and/or CI

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• I have added tests that prove my fix is effective or that my feature works
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Further Comments

It the testing section, I fairly aggressively delete schema files to force rabbit_table:needs_default_data() returns true. There might be more elegant solutions?