fix(db): migrate script loads repo-root .env (#16)

`pnpm migrate:dev` from a clean shell failed with "DATABASE_URL_ADMIN
is not set" because the runner only read process.env and nothing loaded
.env. Load the repo-root .env via process.loadEnvFile() before reading
the vars - anchored to the script's own path, since `pnpm --filter`
runs with packages/db as the cwd. A missing .env is swallowed, so CI
and production (which set the vars directly) are unaffected.

Verified from a clean shell with nothing exported:
  - .env present, DB already migrated -> exit 0, no error
  - DATABASE_URL_ADMIN sourced only from .env -> applies all 13
  - no .env + var exported -> works
  - no .env + nothing set -> the intended "not set" error, no crash


Claude-Session: https://claude.ai/code/session_01Puf9jhj137U3iswf4GWZkG

Signed-off-by: Matthew Wren <info@origindev.com>
Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

Author: OriginDevIT

packages/db/src/migrate.ts

@@ -4,9 +4,14 @@
  * (DATABASE_URL_ADMIN, falling back to DATABASE_URL for single-URL setups).
  *
  *   pnpm --filter @osds/db migrate      # or, from the repo root: pnpm migrate:dev
+ *
+ * Loads the repo-root .env first, so it works from a clean shell with nothing
+ * exported. A real environment (CI, production) sets the vars directly and
+ * needs no .env.
  */
 import { promises as fs } from "node:fs";
 import * as path from "node:path";
+import { loadEnvFile } from "node:process";
 import { pathToFileURL } from "node:url";
 import {
   Kysely,
@@ -17,6 +22,15 @@ import {
 } from "kysely";
 import { Pool } from "pg";
 
+// packages/db/src (or dist) -> repo root. Anchored to this file, not the cwd,
+// because `pnpm --filter` runs with the package as the working directory.
+const repoRootEnv = path.resolve(import.meta.dirname, "../../../.env");
+try {
+  loadEnvFile(repoRootEnv);
+} catch {
+  // No .env at the repo root - rely on the ambient environment.
+}
+
 const migrationFolder = path.join(import.meta.dirname, "migrations");
 
 /** Loads ./migrations/NNNN_*.{ts,js} via file:// URLs so it also works on Windows. */