fix: patch production snapshot vulnerabilities

[iamjr15]

Summary

• refresh the pinned Debian snapshot and upgrade installed OS packages
• align repository, development image, templates, and sandbox runtime on pnpm 11.15.0
• force patched undici 6.27.0 in the isolated sandbox package-manager bundle

Plan

This is a release-blocking security correction within the existing sandbox snapshot architecture documented in plan.md.

What's Included

Runtime security

• move the reproducible Debian snapshot to the patched July 18 archive
• apply snapshot upgrades before installing runtime packages
• eliminate the vulnerable undici copy bundled by the previous pnpm release

Version alignment

• pin pnpm 11.15.0 in root, web, development image, app templates, and documentation
• update the isolated npm package-manager lockfile

Decisions Made

Decision	Choice	Alternatives Considered	Reasoning
OS remediation	refresh the immutable Debian snapshot and upgrade from it	install individual security packages	preserves reproducibility while applying the complete patched package set
undici remediation	upgrade pnpm and add the package-manager override	mutate pnpm internals after install	keeps every installed package manager artifact on supported, auditable versions
release flow	use the protected snapshot workflow after merge	publish manually with Daytona CLI	preserves required provenance, scans, smoke checks, and environment approval

Edge Cases Handled

Scenario	Handling
pnpm embeds its own undici copy	pnpm 11.15.0 contains undici 6.27.0 and the npm install is also overridden
stale Debian base packages remain after snapshot refresh	explicit package upgrade runs before runtime dependency installation
template/runtime version drift	every repository and container pnpm pin is aligned

How to Review

1. Review infra/containers/sandbox/Dockerfile for the reproducible OS update.
2. Review infra/containers/sandbox/package-manager/ for the pnpm and undici remediation.
3. Confirm the remaining pin changes are mechanical version alignment.

Test Plan

• pnpm lint
• pnpm typecheck
• pnpm build
• exact production Docker image build
• protected-workflow-equivalent runtime smoke checks
• Trivy Dockerfile configuration scan
• Trivy HIGH/CRITICAL vulnerability scan
• Trivy secret scan
• isolated package-manager npm audit --omit=dev

After merge, the exact-main static checks and protected Production snapshot workflow remain required before Daytona publication.