Wiring organizations entity with Backend Database, with a TSV fallback

[Shikhar16078]

Summary: Wires the Organization entity onto the PostgREST API introduced by the backend migration, following the same pattern established for Territory: try the API first when VITE_API_URL is configured, fall back to organizations.tsv on any failure. This is one entity's slice of the wider migration.

Changes

• User experience
  • None visible. Same organization data renders regardless of source; only where the data comes from changes.
• Logical changes
  • loadOrganizations() now tries loadOrganizationsFromApi() first when the API is enabled, and falls back to the TSV file (with a console warning) if that fails.
  • New loadOrganizationsFromApi.ts maps the organization + embedded entity rows from PostgREST onto OrganizationData, matching parseOrganizationLine's exact behavior — including its quirks (hqID stays '' rather than undefined when absent; names uses a truthy filter, dropping empty strings as well as null/undefined).
  • Organizations turned out simpler to move than territories: no derived/rolled-up values to withhold, IDs already arrive in the exact string shape the frontend expects (org.-prefixed ids, bare territory codes), and there are no supplemental TSV files to skip.
• Data
  • No data files changed. Reads the same organization/entity tables the ETL already populates from organizations.tsv.
• Refactors
  • Extracted a shared orUndefined() helper into apiConfig.ts (Territory's loader keeps its own private copy, left untouched — out of scope for this PR).

Out of scope/Future work: Territory still has no fallback to TSV on this branch if its API call fails — that work is on a separate, unmerged branch. This PR does not touch Territory. Two known, pre-existing issues are also explicitly not addressed here: a React StrictMode double-invoke race in DataProvider.tsx, and an API response of [] being read as a successful (if empty) load. Both belong in their own PR.

Test Plan

How to test the changes in this PR: Start the local backend (brew services start postgresql@18, then postgrest backend/tools/postgrest.conf), set VITE_API_URL=http://localhost:3000 in .env, run npm run dev, and load any Organization page/detail view. Stop PostgREST and reload — organizations should still populate via the TSV fallback, with Organization API load failed; falling back to TSV files. in the console and no "Error loading data" alert.

Checklist

Summary

• Clear description of what and why
• Scope kept focused; note follow-ups if any
• Set yourself as assignee

Testing

• npm run lint
• npm run build — passes for this PR's own files; a pre-existing type error in a teammate's loadLanguagesFromApi.test.ts currently blocks the full tsc -b on migration/backend itself, unrelated to this change
• npm run test — 434 passed, 0 failed, 11 skipped (gated live-backend parity tests)
  • Tests added or updated for changed logic (loadOrganizationsFromApi.test.ts, loadOrganizationsParity.test.ts, loadOrganizations.test.ts)
• npm run dev -- tried out the website directly
  • Write comments on manual testing: confirmed both the API-success path and the API-down TSV fallback path manually, including the console warning firing correctly on failure.

Changes

Visual changes

• Purely new views can just include the "after" screenshot. (No new views — data source only.)
• Since more views can be reproduced by just sharing the URL -- add links to the relevant page and/or conditions to reproduce the view.

Data changes

• TSV, SVG, etc. edits in public/data/
• Corresponding readmes updated in public/data/
• Load/connect/compute updates in src/features/data/ including how we aggregate data or compute derived values

Internal changes

• Logical changes
• Refactors, moving files around
• If you notice any changes that require explanations, make sure to include the explanations in the code as well.

Docs

• Code is self-documenting, or if not, comments are added where needed.
• Updated markdown readme files documenting how the code behaves or how to develop in case there are any relevant changes to make (docs/api-data-source.md).

[github-actions]

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