chore(db): finish Prisma cutover to Drizzle Kit tooling

Move CMS SQL to drizzle/migrations, drop prisma packages/schema, wire drizzle-kit scripts, and regenerate schema names from src/db/schema.ts.

Co-authored-by: Cursor <[email protected]>

src/lib/foundation/action.ts

@@ -249,14 +249,6 @@ export function handleActionError(error: unknown): ActionFailure {
 	if (error instanceof Error && error.name === "ZodError") {
 		return fail("Validation failed");
 	}
-	if (
-		error instanceof Error &&
-		(error.constructor.name === "PrismaClientKnownRequestError" ||
-			error.name === "PrismaClientKnownRequestError") &&
-		(error as Error & { code?: string }).code === "P2025"
-	) {
-		return fail("Not found");
-	}
 
 	reportError(error, "Action error");
 	return fail("Internal server error");