chore: update firewall image to 2.9.12

[socket-release-bot]

Updates deployment defaults to the published Socket Firewall image 2.9.12 and bumps the Helm chart patch version.

Image: socketdev/socket-registry-firewall:2.9.12
Release run

Manual review is required before merging:

• Review the release changes for configuration or behavioral changes.
• Update deployment documentation and migration examples where needed.
• Check the Helm chart version and CloudFormation defaults, including other pending version PRs.

---

Note

Low Risk
Version-pin and documentation-only updates; no application code or deployment behavior changes beyond the new image tag.

Overview
Bumps the default Socket Registry Firewall container image from 2.9.10 to 2.9.12 and aligns the Helm chart patch release to 0.11.9 (appVersion / image.tag).

The same pins are applied across Helm (Chart.yaml, values.yaml, README defaults), CloudFormation EKS (firewall-eks.yaml parameters ChartVersion and FirewallImageTag, example dns-override.values.yaml), and cloudformation/README.md install-time defaults—no runtime or template logic changes.

^{Reviewed by Cursor Bugbot for commit e0aa77a. Configure here.}