Polish next app navigation and settings UI

[ejsmith]

Summary

• Rework the Next app navigation and command palette around top-level Events, Issues, Sessions, Settings, and saved views.
• Clean up account/settings pages, grid actions, saved-view controls, tab styling, and chart shadows for a flatter, denser UI.
• Add filtered organization listing support with API/test/http coverage used by the organization list experience.
• Update Aspire from 13.3.3 to 13.3.4, including the matching Browsers preview package and Aspire CLI pin.
• Pin build/Docker .NET versions to SDK 10.0.300 and ASP.NET runtime 10.0.8.

Upgrade Notes

• Aspire 13.3.4 is a patch release; no migration-sensitive symbols were found for --log-level, NameOutput, AksSkuTier, AddAndPublishPromptAgent, Aspire.Hosting.NodeJs, or deprecated TypeScript AppHost environment helpers.
• Aspire.Hosting.Browsers remains preview-only, so it was moved to the matching 13.3.4-preview.1.26268.8 build.
• .NET 10.0.8 is the current servicing runtime patch and SDK 10.0.300 is the current GA SDK feature band.

Validation

• cd src/Exceptionless.Web/ClientApp && npm run lint
• cd src/Exceptionless.Web/ClientApp && npm run check
• cd src/Exceptionless.Web/ClientApp && npm run build
• dotnet build src/Exceptionless.AppHost/Exceptionless.AppHost.csproj --artifacts-path artifacts/copilot-aspire-build /property:GenerateFullPaths=true /consoleloggerparameters:NoSummary
• dotnet test tests/Exceptionless.Tests/Exceptionless.Tests.csproj --artifacts-path artifacts/copilot-dotnet-test -- --filter-class Exceptionless.Tests.Controllers.OrganizationControllerTests
• dotnet package list --project src/Exceptionless.AppHost/Exceptionless.AppHost.csproj --vulnerable
• dotnet package list --project tests/Exceptionless.Tests/Exceptionless.Tests.csproj --vulnerable
• docker build --target api --build-arg MinVerVersionOverride=0.0.0-copilot -t exceptionless-api-dotnet-update .
• git diff --check

[github-actions]

Package	Line Rate	Branch Rate	Complexity	Health
Exceptionless.Web	60%	46%	3910	➖
Exceptionless.AppHost	18%	9%	82	❌
Exceptionless.Insulation	25%	23%	203	❌
Exceptionless.Core	67%	61%	7733	➖
Summary	63% (12762 / 20380)	55% (6322 / 11468)	11928	➖