Fix template issues and change default framework to net10.0

[glen-84]

Summary of the changes (Less than 80 chars)

• Fix template issues and change default framework to net10.0.

[Copilot]

Pull request overview

Updates the .NET templates to fix target-framework token replacement and to make .NET 10 (net10.0) the default framework when instantiating templates.

Changes:

• Switch template schema references from http to https in template manifests.
• Update template Framework symbol default from net8.0 to net10.0 (server/gateway/azure-function).
• Adjust the gateway template project to use net8.0 as the replace-token baseline (so the template’s replaces: "net8.0" mechanism works reliably).

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
templates/server/.template.config/template.json	Sets schema URL to HTTPS and changes default framework choice to net10.0.
templates/gateway/HotChocolate.Template.Gateway.csproj	Changes the template’s baseline TFM to net8.0 so it can be replaced by the Framework parameter.
templates/gateway/.template.config/template.json	Sets schema URL to HTTPS and changes default framework choice to net10.0.
templates/azure-function/.template.config/template.json	Sets schema URL to HTTPS and changes default framework choice to net10.0.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (075aae3) to head (0594d45).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@     Coverage Diff      @@
##   main   #9284   +/-   ##
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