[INS-344] Add New Relic Mobile App Token Detector

[mustansir14]

Description:

This PR adds the New Relic Mobile App Token Detector.

Regex: \b((AA[0-9a-f]{40}|eu01xx[0-9a-f]{36})-NRMA)\b

• US region keys start with AA, followed by a 40 characters hexadecimal string, end with "-NRMA"
• EU region keys start with eu01xx, followed by a 36 characters hexadecimal string, end with "-NRMA"

Verification:
For verification, we use the New Relic Android Agent Internal API: https://mobile-collector.newrelic.com. A POST request is made to the /mobile/v5/connect endpoint. If the response status code is 400, it indicates that the key is valid but the request is malformed (since we're not sending a proper payload), while a 401 status code indicates that the key is invalid. Any other status code is treated as an error.
This API is not documented, and was discovered by digging into New Relic's Android agent SDK code.
Note: For EU region keys, the host should be https://mobile-collector.eu01.nr-data.net

Corpora Test:
The detector does not appear in the list.

Checklist:

• Tests passing (make test-community)?
• Lint passing (make lint this requires golangci-lint)?

---

Note

Medium Risk
Adds a new secret detector that performs live HTTP verification against an undocumented New Relic endpoint and extends the shared detector type enum, which could affect runtime behavior and build-time protobuf compatibility if mis-specified.

Overview
Adds a new newrelicmobileapptoken detector that matches US/EU New Relic Mobile App tokens and optionally verifies them via a POST to New Relic’s mobile collector endpoint, returning region metadata on verification.

Registers the detector in the default detector set and introduces a new DetectorType_NewRelicMobileAppToken enum value (proto + generated Go), along with unit and integration tests plus a benchmark for detection/verification behavior.

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