Fix scheduling startup backlog catch-up

[sfmskywalker]

Forward-port/main PR for the scheduling startup backlog fix from #7746.

This keeps the same main-targeted change available after #7746 is retargeted to release/3.8.0.

Validation from original PR/session:

• Elsa.Scheduling build
• Elsa.Workflows.Runtime build
• Elsa.Persistence.EFCore build
• Elsa.Scheduling.UnitTests: 50 passed
• Elsa.Http.UnitTests / HttpWorkflowsMiddlewareTests: 6 passed
• Greptile 5/5 with zero unresolved comments

[sfmskywalker]

Main-targeted copy of #7746. #7746 has been retargeted to release/3.8.0; this PR keeps the same scheduling startup backlog fix queued for main.

[greptile-apps]

Greptile Summary

• Removes the private cshells-feedz package source from NuGet.Config.
• Removes the matching cshells-feedz package source mapping entry.
• Leaves CShells* package IDs mapped to the NuGet official source.

Confidence Score: 5/5

The change is small and localized, but the package-source removal can block clean restores for projects that still depend on CShells packages.

The affected configuration and package mapping behavior are straightforward to inspect, and the main uncertainty is whether the referenced package versions are currently available from the remaining source in all restore environments.

Files Needing Attention: NuGet.Config

T-Rex Logs

What T-Rex did

• Attempted a clean isolated restore harness for src/common/Elsa.Features/Elsa.Features.csproj to verify the restore path, but the run was blocked because dotnet tooling was not installed.
• Tried the scheduling catch-up tests on base and head checkouts; both attempts ended with dotnet: command not found and exit code 127, blocking progress.
• Attempted the advertised build and test commands on the head checkout, but they failed immediately due to the same missing dotnet tooling.
• Artifacts were saved to document the blocked restore harness and the dotnet-not-found outcomes for review.

_{Ran code and verified through T-Rex}

Comments Outside Diff (1)

1. NuGet.Config, line 11-14 (link)

   CShells restore breaks

   The repo still pins and references several CShells* packages, but this config now only allows those package IDs to come from the NuGet official source. A clean restore for projects such as Elsa.Features, Elsa.Shells.Api, or Elsa.ModularServer.Web can fail when the pinned CShells packages are only available from the removed Feedz source or from a local cache. Keep the cshells-feedz source and mapping until the pinned packages are available from NuGet.org, or move the package versions to a source that this config still permits.

   Prompt To Fix With AI

   This is a comment left during a code review.
   Path: NuGet.Config
   Line: 11-14
   
   Comment:
   **CShells restore breaks**
   
   The repo still pins and references several `CShells*` packages, but this config now only allows those package IDs to come from the NuGet official source. A clean restore for projects such as `Elsa.Features`, `Elsa.Shells.Api`, or `Elsa.ModularServer.Web` can fail when the pinned `CShells` packages are only available from the removed Feedz source or from a local cache. Keep the `cshells-feedz` source and mapping until the pinned packages are available from NuGet.org, or move the package versions to a source that this config still permits.
   
   ---
   
   For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

Prompt To Fix All With AI

### Issue 1
NuGet.Config:11-14
**CShells restore breaks**

The repo still pins and references several `CShells*` packages, but this config now only allows those package IDs to come from the NuGet official source. A clean restore for projects such as `Elsa.Features`, `Elsa.Shells.Api`, or `Elsa.ModularServer.Web` can fail when the pinned `CShells` packages are only available from the removed Feedz source or from a local cache. Keep the `cshells-feedz` source and mapping until the pinned packages are available from NuGet.org, or move the package versions to a source that this config still permits.

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

_{Reviews (3): Last reviewed commit: "Merge remote-tracking branch 'origin/mai..." | Re-trigger Greptile}

[sfmskywalker]

Updated the package source mapping so the already-pinned CShells 0.0.28 stable packages restore from NuGet.org instead of the stale cshells Feedz source.\n\nValidation:\n- dotnet restore src/modules/Elsa.Persistence.EFCore.Common/Elsa.Persistence.EFCore.Common.csproj --ignore-failed-sources --no-cache --verbosity minimal\n- dotnet build src/modules/Elsa.Persistence.EFCore.Common/Elsa.Persistence.EFCore.Common.csproj --no-restore --configuration Release --verbosity minimal