chore(data-warehouse): clarify release-status guidance in warehouse-source skill

[Gilbert09]

Problem

The implementing-warehouse-sources skill framed unreleasedSource=True as the default state to set while building a source, and only described removing it as part of a "full release" later. unreleasedSource=True hides a connector from users entirely (the frontend filters out every source where it's truthy), so a finished-but-still-flagged source ships invisible. In practice, newly implemented sources were landing with the flag left in, hiding them from the source picker.

A first pass at fixing the wording over-corrected — it read as though removing the flag were a special, gated step that needed explicit justification.

Changes

Reworked the release-status guidance (step 13 and the implementation checklist) in .agents/skills/implementing-warehouse-sources/SKILL.md so that:

• A finished source having no unreleasedSource flag is the unremarkable default — removing the line the scaffolded stub ships with is just part of finishing, not a permissioned action.
• Keeping unreleasedSource=True is the exception that needs a reason (genuinely incomplete / landed across multiple PRs).
• Adds the "why it matters" (the flag hides the connector) as supporting context rather than the headline.
• Preserves the existing rule to set releaseStatus via the ReleaseStatus enum rather than string literals.

Documentation/agent-instructions only — no production code changes.

How did you test this code?

No automated tests apply — this is a skill markdown file. Verified the merge with upstream's concurrent ReleaseStatus-enum edit resolved cleanly (no conflict markers) and that the release-status guidance reads consistently across step 13 and the checklist.

[greptile-apps]

_{Reviews (1): Last reviewed commit: "chore(data-warehouse): clarify release-s..." | Re-trigger Greptile}

[github-actions]

Purely a documentation clarification in a skill markdown file — no production code, no logic, no API or data model changes. Author not on owning team but the change is a non-behavioral comment/guidance update, which is explicitly fine per ownership rules.

New commits pushed (delta classified non_linear_history) — stamphog approval dismissed; re-review running automatically.

[github-actions]

Purely a documentation clarification in a skill markdown file — no production code, API contracts, or data models changed. Author not on the owning team, but the change is a non-behavioral guidance update, which is explicitly fine per ownership rules.

[deployment-status-posthog]

Deploy status

Environment	Status	Deployed At	Workflow
dev	✅ Deployed	2026-06-03 11:41 UTC	Run
prod-us	✅ Deployed	2026-06-03 12:05 UTC	Run
prod-eu	✅ Deployed	2026-06-03 12:09 UTC	Run