indexer: treat 0.0.0.0 as wildcard source in enriched-view source_match_status

[ben-malbeclabs]

Context

enriched_ip_mroute, enriched_ip_msdp_pim_sa_cache, and enriched_ip_msdp_sa_cache each set source_match_status via:

CASE
    WHEN pub.pk != '' THEN 'publisher_matched'
    WHEN source_address = '' OR source_address = '*' THEN 'group_only'
    ELSE 'unknown_source'
END

PIM uses 0.0.0.0 as the wildcard source on the RP-shared tree (*,G) entry. The CASE doesn't recognise 0.0.0.0 as a wildcard, so those rows fall through to unknown_source — which in turn produces a spurious unknown_source anomaly in /delivery-tree for every (*,G) row.

Caught during vihu's verify run against testnet group tiredsolid (233.84.178.6): source_address = 0.0.0.0 reported unknown_source instead of the correct group_only.

Fix

Extend the wildcard check to include 0.0.0.0 in all three views. One-line change per view via a migration that re-creates them.

Acceptance

• (*,G) rows (source_address in '', '*', or '0.0.0.0') report source_match_status = 'group_only'.
• /delivery-tree no longer emits unknown_source anomalies for the wildcard entries.
• Test added (synthetic mroute row with source_address = '0.0.0.0') covering the case.

Source

Introduced in #619 / #620.