v0.133.0: a restore-test can never fill a box's disk; leftovers retried on a timer (R-672, R-673)

Space preflight before anything is created (uncompressed size from the vzdump log / PBS
snapshot, x1.2 + 5 GiB, thin metadata, off the tested guest's pool when another storage
is eligible, unknown refuses, reported as a non-pass result). Failed scratch teardown and
the stale-lock sweep retried every 10 min (the sweep under the heavy-op gate). A thin
pool crossing 90% requests an immediate host report. Six red-proofs.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

internal/hub/report.go

@@ -470,6 +470,10 @@ type RestoreTest struct {
 	// mount layout, not just booted. Additive — a hub that predates them ignores the unknown keys.
 	MountParity    string   `json:"mount_parity,omitempty"`
 	MountInventory []string `json:"mount_inventory,omitempty"`
+	// Skipped (R-672, v0.133.0): the test did NOT run — the space preflight refused, and Error says
+	// why ("skipped: not enough space on …"). Pass is false. A hub that predates the key reads a
+	// failed test with that error, which is the honest reading.
+	Skipped bool `json:"skipped,omitempty"`
 }
 
 // PBSSnapshot is one PBS (offsite) snapshot's inventory + integrity state (doc 03 §8, slice