fix: close concurrent-insert duplicate-URL race on poi_news

[fatherlinux]

Summary

saveNewsItems dedups news with a SELECT-then-INSERT that has no DB-level guard. Two collection branches processing the same URL concurrently (e.g. a regional article relevant to several nearby POIs, or the same page reached via two link paths) both read "not present" and both insert — producing duplicate pending items in the moderation queue. Investigation against prod found this firing prolifically during multi-POI runs (a single run created ~16 duplicate pending pairs; 69 dup groups / 81 redundant rows accumulated after the monthly collection).

Fix

• migration 069 — partial UNIQUE index on normalized source_url (LOWER(REGEXP_REPLACE(source_url,'/+$','')), WHERE source_url IS NOT NULL), plus an idempotent, status-aware safety-net DELETE that collapses any pre-existing duplicates (keeps published > pending > rejected, one row per URL → preserves dedup tombstones). Events are intentionally excluded — distinct events legitimately share a generic source URL (a venue homepage/calendar).
• newsService.js — ON CONFLICT DO NOTHING + rowCount check, so a lost race logs as a duplicate instead of erroring. Exactly one insert wins; never zero, never two.

Also: 3 unrelated pre-existing test fixes (surfaced by the run)

• ogShareImages — assert the real source-image → POI-photo → brand priority for news permalinks (PR feat: source article image for news/event share previews #385 behavior) instead of an unconditional POI thumbnail.
• ui.integration (2× More Info link) — open a POI that has a more_info_link via its bare-path permalink /<slug> instead of clicking an arbitrary first marker, which now often lands on an amenity POI with no link.

Test plan

• ./run.sh test → 30 files, 370 passed, 1 skipped, 0 failed.
• Migration 069 validated against prod in a rolled-back transaction: safety-net DELETE collapses dups, index builds, and ON CONFLICT DO NOTHING no-ops a duplicate insert without error.
• Gourmand: 0 violations.

🤖 Generated with Claude Code

[gemini-code-assist]

Code Review

This pull request addresses a concurrent-insert duplicate-URL race condition on the poi_news table by introducing a unique index on normalized source URLs and handling conflicts gracefully in newsService.js using ON CONFLICT DO NOTHING. Additionally, integration tests have been updated to ensure more deterministic behavior when testing UI elements and share images. Regarding the database migration, the current self-join approach for deleting pre-existing duplicates can be highly inefficient on large tables; it is recommended to optimize this query using a window function like ROW_NUMBER() to perform the cleanup in a single pass.

[gemini-code-assist]

Using a self-join with USING to delete duplicates can be highly inefficient on large tables because it requires an $O(N^2)$ comparison of all rows matching the join condition.

A more performant and standard PostgreSQL approach is to use a subquery with ROW_NUMBER(). This scans the table once, partitions and sorts the rows, and deletes all but the first row in each partition.

Suggested change

	DELETE FROM poi_news a
	USING poi_news b
	WHERE a.source_url IS NOT NULL
	AND b.source_url IS NOT NULL
	AND LOWER(REGEXP_REPLACE(a.source_url, '/+$', '')) = LOWER(REGEXP_REPLACE(b.source_url, '/+$', ''))
	AND (CASE a.moderation_status WHEN 'published' THEN 0 WHEN 'pending' THEN 1 ELSE 2 END, a.id)
	> (CASE b.moderation_status WHEN 'published' THEN 0 WHEN 'pending' THEN 1 ELSE 2 END, b.id);
	DELETE FROM poi_news
	WHERE id IN (
	SELECT id
	FROM (
	SELECT id,
	ROW_NUMBER() OVER (
	PARTITION BY LOWER(REGEXP_REPLACE(source_url, '/+$', ''))
	ORDER BY CASE moderation_status WHEN 'published' THEN 0 WHEN 'pending' THEN 1 ELSE 2 END, id
	) as rn
	FROM poi_news
	WHERE source_url IS NOT NULL
	) t
	WHERE rn > 1
	);