fix(installer): harden Secure Boot resume unit quoting and USER lookup

[patil2001]

Summary

ods rollback computed compose flags before restoring, then reused them for up -d. When an update changed stack-shaping values (ODS_MODE, TIER, GPU_BACKEND, enabled extensions), rollback reported success while recreating the abandoned configuration's stack — restored cloud mode still booting local llama-server, or an amd restore without its overlay. Flags are now recomputed from the restored .env between restore and restart.

Behavior and invariants

Invariant	Implementation
Pre-restore down unchanged	Still uses flags captured before restore
Post-restore stack matches backup	Flags recomputed after successful restore

AI Assistance

AI-assisted control-flow review of cmd_rollback. The author traced the flag lifecycle and is responsible for the final diff.

Release Lane

• Stable hotfix targeting release/2.6.x
• Mainline change targeting main
• Next-minor work targeting the next feature/minor release
• Not sure; reviewer should help classify

Stable hotfix reason:

Not targeting the stable release branch directly.

Changed Surface

• Docs only
• Tests only
• Dashboard UI
• Installer
• Core runtime
• Dashboard API
• CI workflows

Validation

• bash -n ods/ods-cli - passed.