feat(api): GET/POST /api/v1/yachts

Add yacht list + create routes, export RouteHandler type and inner
handlers so tests can invoke them directly with a mock AuthContext.
New tests/helpers/route-tester.ts provides makeMockCtx/makeMockRequest
reusable by subsequent Task 3.x routes.

src/lib/api/helpers.ts

@@ -3,12 +3,7 @@ import { NextRequest, NextResponse } from 'next/server';
 
 import { auth } from '@/lib/auth';
 import { db } from '@/lib/db';
-import {
-  portRoleOverrides,
-  ports,
-  userPortRoles,
-  userProfiles,
-} from '@/lib/db/schema';
+import { portRoleOverrides, ports, userPortRoles, userProfiles } from '@/lib/db/schema';
 import { type RolePermissions } from '@/lib/db/schema/users';
 import { createAuditLog } from '@/lib/audit';
 import { errorResponse } from '@/lib/errors';
@@ -40,7 +35,7 @@ export interface AuthContext {
   userAgent: string;
 }
 
-type RouteHandler<T = unknown> = (
+export type RouteHandler<T = unknown> = (
   req: NextRequest,
   ctx: AuthContext,
   params: Record<string, string>,
@@ -133,10 +128,7 @@ export function withAuth(
 
       if (!profile.isSuperAdmin && portId) {
         const portRole = await db.query.userPortRoles.findFirst({
-          where: and(
-            eq(userPortRoles.userId, profile.userId),
-            eq(userPortRoles.portId, portId),
-          ),
+          where: and(eq(userPortRoles.userId, profile.userId), eq(userPortRoles.portId, portId)),
           with: {
             role: true,
             port: true,
@@ -182,8 +174,7 @@ export function withAuth(
           email: session.user.email,
           name: session.user.name,
         },
-        ipAddress:
-          req.headers.get('x-forwarded-for')?.split(',')[0]?.trim() ?? 'unknown',
+        ipAddress: req.headers.get('x-forwarded-for')?.split(',')[0]?.trim() ?? 'unknown',
         userAgent: req.headers.get('user-agent') ?? 'unknown',
       };
 
@@ -213,9 +204,7 @@ export function withPermission(
 ): RouteHandler {
   return async (req, ctx, params) => {
     if (!ctx.isSuperAdmin) {
-      const resourcePerms = ctx.permissions?.[resource] as
-        | Record<string, boolean>
-        | undefined;
+      const resourcePerms = ctx.permissions?.[resource] as Record<string, boolean> | undefined;
 
       if (!resourcePerms || !resourcePerms[action]) {
         logger.warn({ userId: ctx.userId, resource, action }, 'Permission denied');