style: gofmt normalization — no logic changes

gofmt -w across the controller tree (46 files) so gofmt -l is empty — disarms the
formatting landmine where a targeted edit + accidental gofmt -w swept ~46 unrelated
files. Pure formatting: whitespace + gofmt's optional-semicolon removal in reflowed
inline closures. One doc comment reworded ('' -> 'the empty string') to avoid gofmt's
Go-1.19 doc-comment typographic substitition ('' -> curly quote) muddying its meaning.
No build/vet/test behavior change.

controller/internal/web/escrow_handlers.go

@@ -152,7 +152,7 @@ func (s *Server) escrowPreflightAPIHandler(w http.ResponseWriter, r *http.Reques
 	agentOK := escrowAgentSupported(agent.AgentVersion())
 	escrowJSON(w, http.StatusOK, map[string]any{
 		"ok": pf.OK && agentOK, "items": pf.Items,
-		"agent_supported": agentOK,
+		"agent_supported":   agentOK,
 		"offbox_configured": s.backupMgr != nil && s.backupMgr.OffboxConfigured(),
 		"escrow_state":      escrowState,
 		"stale":             s.escrowStale(),