feat: Added gatekeeper status interval to config

[macterra]

Added KC_GATEKEEPER_STATUS_INTERVAL to gatekeeper configuration, defaults to 5 minutes between status reports.

Also refactored checkDIDs to group the DID type counts under a new byType header, adding agents and assets:

./admin get-status
{
    "uptimeSeconds": 17,
    "dids": {
        "total": 10609,
        "byType": {
            "agents": 3605,
            "assets": 7004,
            "confirmed": 10029,
            "unconfirmed": 580,
            "ephemeral": 1,
            "invalid": 0
        },
        "byRegistry": {
            "TESS": 2579,
            "hyperswarm": 1730,
            "TBTC": 3117,
            "TFTC": 3159,
            "local": 24
        },
        "byVersion": {
            "1": 9457,
            "2": 678,
            "3": 293,
            "4": 52,
            "5": 32,
            "6": 17,
            "7": 15,
            "8": 10,
            "9": 8,
            "10": 4,
            "11": 4,
            "12": 8,
            "13": 3,
            "14": 1,
            "15": 2,
            "16": 5,
            "18": 4,
            "22": 3,
            "23": 1,
            "25": 2,
            "31": 1,
            "33": 1,
            "37": 1,
            "42": 1,
            "44": 1,
            "50": 1,
            "56": 1,
            "61": 1,
            "62": 1,
            "64": 1
        }
    },
    "memoryUsage": {
        "rss": 148160512,
        "heapTotal": 78000128,
        "heapUsed": 55464728,
        "external": 25333966,
        "arrayBuffers": 22856048
    }
}

gatekeeper-1  | Status -----------------------------
gatekeeper-1  | DID Database (redis):
gatekeeper-1  |   Total: 10609
gatekeeper-1  |   By type:
gatekeeper-1  |     Agents: 3605
gatekeeper-1  |     Assets: 7004
gatekeeper-1  |     Confirmed: 10029
gatekeeper-1  |     Unconfirmed: 580
gatekeeper-1  |     Ephemeral: 1
gatekeeper-1  |     Invalid: 0
gatekeeper-1  |   By registry:
gatekeeper-1  |     TBTC: 3117
gatekeeper-1  |     TESS: 2579
gatekeeper-1  |     TFTC: 3159
gatekeeper-1  |     hyperswarm: 1730
gatekeeper-1  |     local: 24
gatekeeper-1  |   By version:
gatekeeper-1  |     1: 9457
gatekeeper-1  |     2: 678
gatekeeper-1  |     3: 293
gatekeeper-1  |     4: 52
gatekeeper-1  |     5: 32
gatekeeper-1  |     6+: 97
gatekeeper-1  | Memory Usage Report:
gatekeeper-1  |   RSS: 136.90 MB (Resident Set Size - total memory allocated for the process)
gatekeeper-1  |   Heap Total: 69.52 MB (Total heap allocated)
gatekeeper-1  |   Heap Used: 38.80 MB (Heap actually used)
gatekeeper-1  |   External: 22.40 MB (Memory used by C++ objects bound to JavaScript)
gatekeeper-1  |   Array Buffers: 20.03 MB (Memory used by ArrayBuffer and SharedArrayBuffer)
gatekeeper-1  | Uptime: 368s (6 minutes, 8 seconds)
gatekeeper-1  | ------------------------------------