feat(admin): add addresses + geocoding to organizations

[cdcore09]

Summary

Organizations need addresses so they can be placed on the community map alongside members. Addresses must be geocoded to lat/long so the map can render them without per-request lookups, mirroring the existing pattern on profiles (latitude/longitude + showOnMap).

Requirements

• Add address columns to organizations (street/city/region/country/postalCode + latitude numeric(9,6) + longitude numeric(9,6) + showOnMap boolean)
• Migration: backfill latitude/longitude as nullable; existing rows stay null until geocoded
• Geocoding pipeline (Nominatim or Mapbox — pick one and document) triggered on address change in admin PATCH
• Admin UI: address fields on the org detail page Identity tab + a read-only "Geocoded to: ${lat}, ${lng}" preview with a re-geocode button
• Public map (apps/web map surface used by the directory) picks up org pins gated on showOnMap
• showOnMap toggle defaults to false for legacy imports; orgs explicitly approved via admin can flip on

Context

The profiles table already has latitude, longitude, showOnMap, and publicLocation — the org-side schema should mirror those names so map rendering can stay type-uniform across actor kinds.

Implementation Notes

Geocoding is async and the admin shouldn't block on it: store address fields synchronously on PATCH, then enqueue a geocode job. For the v1 a single inline fetch to Nominatim on save is probably acceptable given org volume; we can move to a queued worker later if rate limits bite.