fix(traffic): сохранять точность объёмов и обозначать бинарные единицы

lib/traffic-observations.test.ts

@@ -5,6 +5,9 @@ const row={rxNow:0,txNow:0,rxPeak:0,txPeak:0,rxTotal:0,txTotal:0,rxSeries:[0,0],
 const obs={rxNow:true,txNow:true,rxSeries:[false,true],txSeries:[false,true],sampledAt,currentState:"current",expiresAt}
 assert.equal(projectTrafficObservations(row,at).rxNow,null)
 const known=projectTrafficObservations({...row,observations:obs},at);assert.equal(known.rxNow,0);assert.deepEqual(known.rxSeries,[null,0])
+assert.equal(known.rxTotal,null)
+assert.equal(projectTrafficObservations({...row,volumeUnit:"GiB",observations:obs},at).rxTotal,0)
+assert.throws(()=>projectTrafficObservations({...row,volumeUnit:"GB",observations:obs},at))
 const stale=projectTrafficObservations({...row,observations:obs},at+90_001);assert.equal(stale.rxNow,null);assert.equal(stale.observations?.currentState,"stale");assert.deepEqual(stale.rxSeries,[null,0])
 assert.equal(projectTrafficObservations({...row,observations:{...obs,currentState:"error"}},at).rxNow,null)
 for(const change of [{rxNow:-1},{observations:{...obs,sampledAt:"bad"}},{observations:{...obs,sampledAt:null}},{observations:{...obs,rxSeries:[]}}])assert.throws(()=>projectTrafficObservations({...row,...change},at))