P2 — Remove hardcoded default database credentials from prisma.config.ts

[itsmiso-ai]

Problem

prisma.config.ts:4-6 contains plaintext credentials:

const databaseUrl =
  process.env.DATABASE_URL ?? "postgresql://dispatch:dispatch@localhost:5432/dispatch";

While this is a default fallback for local dev, it's a supply-chain risk if the file is ever included in error reports or screenshots.

Recommended Fix

Remove the fallback entirely; require DATABASE_URL to be set explicitly. Or use a clearly-labeled placeholder like postgresql://user:placeholder@localhost:5432/dispatch.

Acceptance Criteria

• No plaintext credentials in committed source files
• DATABASE_URL is required at runtime (fails with clear error if not set)

Parent: #235 (Weekly tech debt audit: 2026-05-27)

Labels: audit