Bump nginx from 1.25-alpine to 1.29.8-alpine in /infrastructure

Bumps nginx from 1.25-alpine to 1.29.8-alpine.

---
updated-dependencies:
- dependency-name: nginx
  dependency-version: 1.29.8-alpine
  dependency-type: direct:production
...

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Author: dependabot[bot]

infrastructure/Dockerfile.dashboard.optimized

@@ -35,7 +35,7 @@ COPY dashboard-v2/ .
 RUN npm run build
 
 # Final stage - minimal runtime image with nginx
-FROM nginx:1.25-alpine AS runtime
+FROM nginx:1.29.8-alpine AS runtime
 # Install security updates
 RUN apk --no-cache upgrade