Seed CIRNAC community data into source-manager

[jonesrussell]

Context

The source-manager communities table is empty. Minoo's backfill script needs communities with inac_id populated to match against local community records and store NC UUIDs.

The seed-communities CLI tool exists (source-manager/cmd/seed-communities/main.go) but:

1. It's not built into the Docker image (only the main source-manager binary is included)
2. No CIRNAC CSV file is on the server

Steps

1. Download CIRNAC First Nations data CSV from the government open data portal
2. Either:
   • Option A: Build seed-communities into the Docker image and exec inside the container
   • Option B: Run seed-communities from outside Docker with DB credentials pointing at the exposed Postgres port
3. Run seed-communities --csv=<path> to populate the communities table
4. Optionally run seed-municipalities for municipal data

Acceptance Criteria

• GET /api/v1/communities?limit=5 returns community data
• Communities have inac_id populated (needed for Minoo sync)
• At least 600+ First Nation communities seeded