Add AV/Defender tests and clear PROBLEMS.md antivirus rows.

Cover mining diagnostics JSON blockers, AV-Safe preset fields, defender_off error paths, and Calibrate exclusion .ps1 generation with Go + Vitest; honest AV limits already documented in settingHelp.

server/web/vitest.config.ts

@@ -1,6 +1,12 @@
-import { defineConfig } from 'vitest/config';
+import { readFileSync } from 'node:fs'
+import { defineConfig } from 'vitest/config'
+
+const pkg = JSON.parse(readFileSync(new URL('./package.json', import.meta.url), 'utf8')) as { version: string }
 
 export default defineConfig({
+  define: {
+    __APP_VERSION__: JSON.stringify(pkg.version),
+  },
   test: {
     environment: 'node',
     include: ['src/**/*.test.{ts,tsx}'],