Re-include Linux kmod cert in x64 secure boot template

[mebersol]

Trusted Launch VMs should include the Linux kmod certificate for x64

Additionally, add new templates (currently unused) for future confidential scenarios.

[Copilot]

Pull request overview

Updates the x64 Hyper-V Secure Boot template set to support Trusted Launch scenarios that require the Linux kmod certificate, and adds placeholder “confidential” x64 template JSON files for future use.

Changes:

• Re-add the Azure Services Linux Kmod PCA certificate to the x64 MicrosoftUEFICertificateAuthority template’s db.
• Add new (currently unused) x64 “Confidential” template JSON files for Windows and Microsoft UEFI.

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 2 comments.

File	Description
vm/devices/firmware/hyperv_secure_boot_templates/templates/x64/MicrosoftUEFICertificateAuthority_Template.json	Adds the Linux kmod PCA cert to db (aligning x64 with the existing aarch64 template contents).
vm/devices/firmware/hyperv_secure_boot_templates/templates/x64/MicrosoftWindows_Confidential_Template.json	New confidential Windows template JSON (not currently referenced by the resource crate API).
vm/devices/firmware/hyperv_secure_boot_templates/templates/x64/MicrosoftUEFI_Confidential_Template.json	New confidential UEFI template JSON (not currently referenced by the resource crate API).

[Copilot]

These new templates are not referenced by hyperv_secure_boot_templates/src/lib.rs, so they won't be parsed/validated by hyperv_uefi_custom_vars_json::load_template_from_json in unit tests (build.rs only checks JSON syntax via serde_json). Consider adding a lightweight validation test (or wiring them into the template include list) so schema issues are caught now rather than when the templates are first used.

[Copilot]

These new templates are not referenced by hyperv_secure_boot_templates/src/lib.rs, so they won't be parsed/validated by hyperv_uefi_custom_vars_json::load_template_from_json in unit tests (build.rs only checks JSON syntax via serde_json). Consider adding a lightweight validation test (or wiring them into the template include list) so schema issues are caught now rather than when the templates are first used.