EIP-7892: Blob Parameter Only Hardforks - 2nd attempt

[yperbasis]

Restores reverted PR #14843 + changes to the following agreed format:

{
    "blobSchedule": {
        "cancun": {
            "target": 3,
            "max": 6,
            "baseFeeUpdateFraction": 3338477
        },
        "prague": {
            "target": 6,
            "max": 9,
            "baseFeeUpdateFraction": 5007716
        },
        "osaka": {
            "target": 6,
            "max": 9,
            "baseFeeUpdateFraction": 5007716
        },
        "bpo1": {
            "target": 6,
            "max": 9,
            "baseFeeUpdateFraction": 5007716
        },
        "bpo2": {
            "target": 12,
            "max": 18,
            "baseFeeUpdateFraction": 5007716
        },
        "bpo3": {
            "target": 6,
            "max": 9,
            "baseFeeUpdateFraction": 5007716
        },
        "bpo4": {
            "target": 12,
            "max": 18,
            "baseFeeUpdateFraction": 5007716
        },
        "bpo5": {
            "target": 6,
            "max": 9,
            "baseFeeUpdateFraction": 5007716
        }
    },
    "cancunTime": 0,
    "pragueTime": 0,
    "osakaTime": 1747387400,
    "bpo1Time": 1747387400,
    "bpo2Time": 1747387784,
    "bpo3Time": 1747388168,
    "bpo4Time": 1747388552,
    "bpo5Time": 1747388936
}

N.B. Hive EEST tests are green after 05ca140.

[yperbasis]

Waiting for PR #15261 to be merged first