fix: use real DATABASE_URL from .env for migrations in deploy workflow

The deploy job was overwriting DATABASE_URL with a placeholder for
prisma:generate, but this persisted when db:migrate ran later, causing
ER_ACCESS_DENIED_ERROR. Since the stage directory already symlinks to
the live .env, the real DATABASE_URL is available without override.

.gitea/workflows/deploy.yaml

@@ -335,10 +335,10 @@ jobs:
           export DATABASE_POOL_SIZE="${DEPLOY_DATABASE_POOL_SIZE:-5}"
           echo "STAGE DATABASE_POOL_SIZE=${DATABASE_POOL_SIZE}"
 
-          pnpm install --frozen-lockfile
-          export DATABASE_URL="${DEPLOY_DATABASE_URL:-mysql://placeholder:please@localhost/placeholder}"
-          # prisma generate does not need a live DB connection.
-          pnpm prisma:generate
+           pnpm install --frozen-lockfile
+           # Stage symlinks to live .env, so DATABASE_URL is already the real value.
+           # prisma generate only needs the URL for client generation — no live DB connection.
+           pnpm prisma:generate
           export BCRYPT_ROUNDS=4
           pnpm typecheck
           # Validate production env (AUTH_SECRET, DATABASE_URL, …) during build.