feat: comprehensive INFO/WARN/ERROR logging across all controller modules

Add structured operational logging at INFO, WARN, and ERROR levels to
every controller module. Standardize custom prefixes ([GEO], [SCHED],
[SYNC]) to use [INFO/WARN/ERROR] [module] format. Fix misleveled logs
(WARN->ERROR for data loss scenarios, WARN->INFO for routine operations).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

controller/internal/storage/migrate.go

@@ -82,6 +82,9 @@ func MigrateAppData(
 			Error:          errStr,
 			ElapsedSeconds: int(time.Since(start).Seconds()),
 		}
+		if req.Logger != nil {
+			req.Logger.Printf("[ERROR] [storage] Migration %s failed at %s: %v", req.StackName, step, err)
+		}
 		return fmt.Errorf("%s: %w", msg, err)
 	}
 
@@ -91,6 +94,9 @@ func MigrateAppData(
 		}
 	}
 
+	if req.Logger != nil {
+		req.Logger.Printf("[INFO] [storage] Starting migration: stack=%s from=%s to=%s", req.StackName, req.CurrentHDDPath, req.TargetPath)
+	}
 	dbg("starting migration: stack=%s from=%s to=%s mounts=%d", req.StackName, req.CurrentHDDPath, req.TargetPath, len(req.HDDMounts))
 
 	// --- Step 1: Validate ---
@@ -196,6 +202,9 @@ func MigrateAppData(
 		return fail("starting", "Alkalmazás indítása sikertelen az új tárolóról", err)
 	}
 
+	if req.Logger != nil {
+		req.Logger.Printf("[INFO] [storage] Migration completed: stack=%s elapsed=%ds", req.StackName, int(time.Since(start).Seconds()))
+	}
 	dbg("migration completed: stack=%s bytesCopied=%d elapsed=%ds", req.StackName, bytesCopied, int(time.Since(start).Seconds()))
 	send("done",
 		fmt.Sprintf("Áthelyezés kész! Az alkalmazás az új tárolóról fut. (Régi adat: %s, idő: %ds)",