fix: revert relative base path and fix processor table overflow

Revert base: './' back to '/' — relative asset paths break on deep
URLs like /dashboard/app/route where the browser resolves assets to
/dashboard/app/assets/ instead of /assets/.

Also fix processor metrics table clipping: remove flex:1/min-height:0
from .processorSection so the table takes its natural content height
and the page scrolls to show all rows (was clipping at ~12 of 18).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/vite.config.ts

@@ -27,7 +27,7 @@ export default defineConfig({
   optimizeDeps: {
     include: ['swagger-ui-dist/swagger-ui-bundle'],
   },
-  base: './',
+  base: '/',
   build: {
     outDir: 'dist',
   },