Create a new partners access point to flood affected villages

[wadhwamatic]

Summary

Adds a new partner-facing API endpoint that exposes approved flood-affected village data to external partners (starting with IDPoor), without giving them direct access to Kobo.

Closes #278

What's included

• GET /partners/flood-affected-villages?startDate=&endDate= — returns one row per affected village for approved flood submissions in the given disaster-event date range
• API key auth (x-api-key header) via PARTNER_API_KEYS, separate from staff login
• Dedicated Kobo credential (KOBO_PUBLIC_API_TOKEN), isolated from the validation-workflow token
• Village-level gazetteerCode resolution from the flood form's g2/village select-multiple field, backed by a generated villageToCommune lookup table (packages/interfaces/src/kobo/villages.ts)
• Basic request logging (partner, date range, timestamp) for audit purposes
• PARTNER_SKIP_APPROVAL_FILTER local-dev-only escape hatch for testing before any submissions are approved
• Unit tests for PartnersService (query filtering, village expansion, unknown-code handling, pagination)

Design notes

• Approved-only filtering is enforced by the DMP backend's Kobo query, not by Kobo permissions — Kobo's "View submissions" grant doesn't distinguish validation status
• Village → commune mapping can't be derived arithmetically (fails on ~2% of real codes), so it's sourced from an explicit lookup table generated from the live Kobo XLSForm
• No wrapper/gateway beyond this thin module — not justified at current partner scale

Testing

• All existing backend tests pass unaffected
• New PartnersService tests cover the approval filter, village expansion, and pagination
• Manually verified against real Kobo data locally

Follow-ups (tracked separately, not blocking this PR)

• Provision the dedicated Kobo service account to replace personal tokens
• Issue IDPoor a real API key
• Confirm response contract with WebEssentials
• Decide on per-partner geographic scoping if/when partners beyond IDPoor are added

[github-actions]

Build succeeded and deployed:

• GitHub Pages: https://wfp-vam.github.io/dmp/pr-280/
• Surge (deprecated): https://wfp-dmp-280.surge.sh

(hash 52cf790 deployed at 2026-09-09T02:39:25)

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