CI/Docker: use SSL-free Nexus endpoints (mirror serves partial chain)

The HTTPS Nexus serves an incomplete cert chain that container trust stores
reject (NU1301 PartialChain / UNABLE_TO_GET_ISSUER), failing CI restore/install.
- NuGet has no strict-ssl flag → point CI + Dockerfile + compose at the plain-HTTP
  Nexus (http://171.22.25.73:8081, allowInsecureConnections) — no TLS, no cert check.
- npm: add --strict-ssl=false to the CI web-check install (Dockerfile already had it);
  Docker npm registry default also moved to the HTTP Nexus.
- ENV_FILE.example documents NUGET_INDEX/NPM_REGISTRY overrides.

Local dev (Windows trusts the cert) + image base pulls (Docker trusts it) are
unaffected — only in-container package feeds switch to HTTP.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

deploy/ENV_FILE.example

@@ -29,6 +29,12 @@ NEXT_PUBLIC_SERVER_URL=http://localhost:1505
 # Origins allowed by the API's CORS (comma-separated). Must include the web URL.
 CORS_ORIGINS=http://localhost:1500
 
+# Package mirrors used during Docker builds. Default to the plain-HTTP Nexus
+# (no SSL) because the HTTPS mirror serves a partial cert chain that fresh
+# container trust stores reject. Override only if your Nexus moves.
+# NUGET_INDEX=http://171.22.25.73:8081/repository/nuget-group/index.json
+# NPM_REGISTRY=http://171.22.25.73:8081/repository/npm-group/
+
 # ZarinPal (sandbox for now — switch in admin/panel later)
 ZARINPAL_MERCHANT_ID=299685fb-cadf-4dfc-98e2-d4af5d81528d
 ZARINPAL_SANDBOX=true