Add getConfigSchema to surface K8s fields in Paperclip UI

Adds AdapterConfigSchema with three sections (Kubernetes, Resource Limits,
Scheduling) exposing: namespace, image, imagePullPolicy, kubeconfig,
resources.{requests,limits}.{cpu,memory}, nodeSelector, tolerations,
labels, ttlSecondsAfterFinished, retainJobs.

Paperclip's server fetches GET /api/adapters/:type/config-schema and
caches the result, automatically assigning ConfigFields to external
adapters. The adapter now wires getConfigSchema into createServerAdapter().

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

vitest.config.ts

@@ -0,0 +1,13 @@
+import { defineConfig } from "vitest/config";
+
+export default defineConfig({
+  test: {
+    globals: true,
+    include: ["src/**/*.test.ts"],
+    coverage: {
+      reporter: ["text", "lcov"],
+      include: ["src/**/*.ts"],
+      exclude: ["src/**/*.d.ts", "src/index.ts"],
+    },
+  },
+});