fix: review fixes for MCP and API key feature

- Remove spurious ALTER TABLE client_targets DROP DEFAULT from migration
  (Prisma schema drift side-effect unrelated to this PR)
- Surface revoke errors in ApiKeysPage UI via deleteApiKey.isError
- Fix UpdateProjectInput.color type to allow null, removing unsafe cast
  in the update_project MCP tool handler

backend/prisma/migrations/20260316103132_add_api_keys/migration.sql

@@ -1,6 +1,3 @@
--- AlterTable
-ALTER TABLE "client_targets" ALTER COLUMN "working_days" DROP DEFAULT;
-
 -- CreateTable
 CREATE TABLE "api_keys" (
     "id" TEXT NOT NULL,

backend/src/routes/mcp.routes.ts

@@ -139,15 +139,8 @@ function buildMcpServer(user: AuthenticatedUser): McpServer {
         clientId: z.string().uuid().optional().describe('Move project to a different client'),
       },
     },
-    async (args) => {
-      const { id, ...rest } = args as {
-        id: string;
-        name?: string;
-        description?: string;
-        color?: string | null;
-        clientId?: string;
-      };
-      const project = await projectService.update(id, userId, rest as import('../types').UpdateProjectInput);
+    async ({ id, name, description, color, clientId }) => {
+      const project = await projectService.update(id, userId, { name, description, color, clientId });
       return { content: [{ type: 'text', text: JSON.stringify(project, null, 2) }] };
     }
   );

backend/src/types/index.ts

@@ -31,7 +31,7 @@ export interface CreateProjectInput {
 export interface UpdateProjectInput {
   name?: string;
   description?: string;
-  color?: string;
+  color?: string | null;
   clientId?: string;
 }