Fix repository dashboard accuracy and source links

[ewlarson]

The repository dashboard counted overlapping and archived source memberships as current records, omitted untagged published records from its total, and labeled migrated records as not yet synced. Count unique records in active sources and all published database records, show Archived/Disabled/Active status separately from historical harvest results, and describe overlaps without implying a synchronization failure. Clearly label database counts and their distinction from live index verification.

Normalize GitHub repository links to include the OpenGeoMetadata organization when metadata is incomplete. Add a Search API link to every row using that repository as the active ogm_repo filter. Preserve unknown Aardvark status rather than assuming presence.

Validation:

• 13 focused tests pass, including PostgreSQL integration coverage for duplicates, archived/disabled sources, missing records, publication precedence, URLs, and filter parsing.
• Ruff and diff checks pass.
• Read-only production query verification: 315,135 unique active-source records and 318,408 published records; Minnesota and legacy USGS overlaps match the audit.
• All 52 repository destinations checked against the GitHub catalog, including the legacy USGS redirect.
• Production geobtaa filtered search returns 40,703 records.

No production deployment is included in this PR.