CommandPolicy gains a VerifyWindow (Go duration) bounded to
[(0,], 15m] with a 2m default. NormalizeVerifyWindow and the policy
Normalize() method enforce the bounds; DefaultPolicy() populates the
default. JSON marshaling now goes through a shadow struct so the wire
form serializes as a duration string (e.g. "2m0s") rather than the raw
nanosecond integer.
Tests cover the default, the bounds (clamp to max, fall through to
default for zero/negative), the JSON roundtrip, the unmarshal-applies-
bounds contract, and rejection of unparseable duration strings.
The blocked patterns for 'reboot' and 'shutdown' were too broad,
matching anywhere in the command string. This caused legitimate
Proxmox VM control commands like 'qm reboot 201' to be blocked
instead of requiring approval.
Fix by anchoring these patterns to only match bare system commands
(^reboot, ^shutdown, etc.) while allowing qm/pct variants through
the RequireApproval path.
Related to #1024
rcourtman