feat(windows): add 7b non-sec regkeys

[smiezah-msft]

This PR introduces the July "7B” non-security registry key updates to ensure consistency and compliance with the latest Windows image configuration requirements for AKS node provisioning.
What’s included

Added/updated non-security (non-sec) registry keys aligned with 7B requirements
Ensured keys are applied across relevant Windows SKUs/images used in AgentBaker
Maintained parity with upstream Windows image expectations and servicing guidance

**Why this change
Enables alignment with monthly Patch Tuesday (7B cycle) configuration updates
Ensures AKS node images remain consistent with latest platform expectations
Prevents drift between base OS images and AgentBaker-applied configuration

**Validation
✅ Verified registry key presence post-image bake
✅ Confirmed no regression in image provisioning / node pool creation
✅ Validated against current test pipelines (Hyper-V / containerd scenarios)

**Risk / Impact
Low risk – non-security configuration only
No expected impact to existing workloads or cluster behavior
Changes are scoped strictly to registry configuration

Notes

Follows established monthly release pattern for non-sec updates
Complements security fixes delivered separately in Patch Tuesday cycle

[github-actions]

Changes cached containers or packages on windows VHDs

Please get a Windows SIG member to approve.

The following dif file shows any additions or deletions from what will be cached on windows VHDs organised by VHD type.

• Additions are new things cached.
• Deletions are things no longer cached.

diff --git a/vhd_files/2025-gen2-tl.txt b/vhd_files/2025-gen2-tl.txt
index 5fc7b9e..a901175 100644
--- a/vhd_files/2025-gen2-tl.txt
+++ b/vhd_files/2025-gen2-tl.txt
@@ -33,0 +34 @@ HKLM:\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides\18
+HKLM:\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides\908168846=1
diff --git a/vhd_files/2025-gen2.txt b/vhd_files/2025-gen2.txt
index 5c054c3..4d7aa19 100644
--- a/vhd_files/2025-gen2.txt
+++ b/vhd_files/2025-gen2.txt
@@ -33,0 +34 @@ HKLM:\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides\18
+HKLM:\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides\908168846=1
diff --git a/vhd_files/2025.txt b/vhd_files/2025.txt
index 1fe4b78..1441011 100644
--- a/vhd_files/2025.txt
+++ b/vhd_files/2025.txt
@@ -33,0 +34 @@ HKLM:\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides\18
+HKLM:\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides\908168846=1

[Copilot]

Pull request overview

This PR updates the Windows VHD build configuration (vhdbuilder/packer/windows/windows_settings.json) to include a new July 2026 “7B” non-security registry override, aligning AgentBaker-built Windows images with the latest monthly servicing expectations.

Changes:

• Added a new FeatureManagement\Overrides registry key entry (Name: 908168846, DWORD: 1) for 2025* Windows SKUs.
• Tagged the new entry with a Comment marker (2026-7B) to track the monthly rollout.

[timmy-wright]

Reviewed failing tests, not related to this PR.