Upgrade vulnerable NuGet dependencies flagged by Snyk

[devin-ai-integration]

Summary

Resolves all high-severity Snyk dependency findings by bumping direct packages and adding explicit PackageReferences for two transitives whose fixed versions the EF Core 7.0.x tree doesn't reach on its own.

src/Infrastructure/Infrastructure.csproj:

• Microsoft.EntityFrameworkCore* 7.0.10 → 7.0.20 (pulls Microsoft.Data.SqlClient 5.1.5, System.Drawing.Common 6.0.0)
• Npgsql 7.0.4 → 7.0.7; Npgsql.EntityFrameworkCore.PostgreSQL(.NodaTime) 7.0.4 → 7.0.11
• new explicit Azure.Identity 1.11.4 (SqlClient 5.1.5 only brings 1.10.3, which is still vulnerable to SNYK-DOTNET-AZUREIDENTITY-7246762)
• new explicit System.Text.Json 8.0.5 (Microsoft.Extensions.DependencyModel 7.0.0 pins 7.0.0)

src/WebApi/WebApi.csproj: Microsoft.EntityFrameworkCore.Design 7.0.10 → 7.0.20.

Dockerfile: pin aspnet:7.0 → aspnet:7.0.20 and sdk:7.0 → sdk:7.0.410 (latest .NET 7 patch releases; same major).

.github/workflows/dotnet.yml: dotnet-version: 6.0.x → 7.0.x. The workflow was failing on main too because the runner had no .NET 7 runtime for the net7.0 test hosts; this makes the CI check meaningful again.

Resolved versions in all three project.assets.json verified: Azure.Identity 1.11.4, Microsoft.Data.SqlClient 5.1.5, Npgsql 7.0.7, System.Drawing.Common 6.0.0, System.Text.Json 8.0.5. dotnet build clean, dotnet test 20/20 passing; Snyk PR check passes.

Snyk issues addressed

• SNYK-DOTNET-AZUREIDENTITY-6009155
• SNYK-DOTNET-AZUREIDENTITY-6597976
• SNYK-DOTNET-AZUREIDENTITY-7246762
• SNYK-DOTNET-MICROSOFTDATASQLCLIENT-6149434
• SNYK-DOTNET-NPGSQL-6825563
• SNYK-DOTNET-SYSTEMDRAWINGCOMMON-3063427
• SNYK-DOTNET-SYSTEMTEXTJSON-7433719

Note: .NET 7 is end-of-life, so the base image will still carry OS-package CVEs; moving to .NET 8 would require a major version change and is out of scope here.

Link to Devin session: https://app.devin.ai/sessions/45555d06ec1f4f3086c0eb510b96b9f1
Open in Devin Desktop: https://app.devin.ai/desktop/session/45555d06ec1f4f3086c0eb510b96b9f1?variant=devin

[devin-ai-integration]

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