feat: review flow compound index and/or add a new index for state and flow.cookie

[viniarck]

As I was fixing issue #160, I just realized that clients querying for cookie_range and state without dpid wouldn't hit the compound index, which is the args/query pattern that telemetry_int will use in the future. So, in the future this should be analyzed if a new index will be needed, currently it's hitting the single IXSCAN { flow.cookie: 1 } index, probably wouldn't impact much, but currently it's not ideal:

v2/stored_flows?cookie_range=12284936249945383243&cookie_range=12284936249945383243&state=installed&state=pending

{
    op: 'query',
    ns: 'napps.flows',
    command: {
      find: 'flows',
      filter: {
        state: { '$in': [ 'installed', 'pending' ] },
        'flow.cookie': {
          '$gte': Decimal128("12284936249945383243"),
          '$lte': Decimal128("12284936249945383243")
        }
      },
      sort: { 'flow.priority': -1, updated_at: 1 },
      projection: { _id: false },
      readConcern: { level: 'majority' },
      lsid: { id: new UUID("0f962b7c-d46a-41bb-9b79-e3c1a9f8b49e") },
      '$clusterTime': {
        clusterTime: Timestamp({ t: 1691417103, i: 2 }),
        signature: {
          hash: Binary(Buffer.from("0000000000000000000000000000000000000000", "hex"), 0),
          keyId: Long("0")
        }
      },
      '$db': 'napps',
      '$readPreference': { mode: 'primaryPreferred' }
    },
    keysExamined: 0,
    docsExamined: 0,
    hasSortStage: true,
    fromMultiPlanner: true,
    cursorExhausted: true,
    numYield: 0,
    nreturned: 0,
    queryHash: 'C9307D11',
    planCacheKey: 'A24E0674',
    locks: {
      FeatureCompatibilityVersion: { acquireCount: { r: Long("1") } },
      Global: { acquireCount: { r: Long("1") } },
      Mutex: { acquireCount: { r: Long("1") } }
    },
    flowControl: {},
    readConcern: { level: 'majority', provenance: 'clientSupplied' },
    responseLength: 225,
    protocol: 'op_msg',
    millis: 0,
    planSummary: 'IXSCAN { flow.cookie: 1 }',
    execStats: {
      stage: 'SORT',
      nReturned: 0,
      executionTimeMillisEstimate: 0,
      works: 3,
      advanced: 0,
      needTime: 1,
      needYield: 0,
      saveState: 0,
      restoreState: 0,
      isEOF: 1,
      sortPattern: { 'flow.priority': -1, updated_at: 1 },
      memLimit: 104857600,
      type: 'simple',
      totalDataSizeSorted: 0,
      usedDisk: false,
      inputStage: {
        stage: 'PROJECTION_DEFAULT',
        nReturned: 0,
        executionTimeMillisEstimate: 0,
        works: 1,
        advanced: 0,
        needTime: 0,
        needYield: 0,
        saveState: 0,
        restoreState: 0,
        isEOF: 1,
        transformBy: {},
        inputStage: {
          stage: 'FETCH',
          filter: { state: { '$in': [Array] } },
          nReturned: 0,
          executionTimeMillisEstimate: 0,
          works: 1,
          advanced: 0,
          needTime: 0,
          needYield: 0,
          saveState: 0,
          restoreState: 0,
          isEOF: 1,
          docsExamined: 0,
          alreadyHasObj: 0,
          inputStage: {
            stage: 'IXSCAN',
            nReturned: 0,
            executionTimeMillisEstimate: 0,
            works: 1,
            advanced: 0,
            needTime: 0,
            needYield: 0,
            saveState: 0,
            restoreState: 0,
            isEOF: 1,
            keyPattern: { 'flow.cookie': 1 },
            indexName: 'flow.cookie_1',
            isMultiKey: false,
            multiKeyPaths: { 'flow.cookie': [] },
            isUnique: false,
            isSparse: false,
            isPartial: false,
            indexVersion: 2,
            direction: 'forward',
            indexBounds: { 'flow.cookie': [Array] },
            keysExamined: 0,
            seeks: 1,
            dupsTested: 0,
            dupsDropped: 0
          }
        }
      }
    },
    ts: ISODate("2023-08-07T14:05:16.783Z"),
    client: '172.18.0.1',
    allUsers: [ { user: 'napp_user', db: 'napps' } ],
    user: 'napp_user@napps'
  }