set scanType to socket_tier1 when creating reachability full scans

[mtorp]

The scan_type is set to 'socket_tier'. This change allows us to distinguish Tier 1 scans from regular full scans, and is a requirement for proper ingestion of Tier 1 alerts into organization-wide alerts.

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Note

• Plumbs scan_type into fetchCreateOrgFullScan and sets it in handle-create-new-scan to constants.SCAN_TYPE_SOCKET_TIER1 when reachability is enabled, otherwise constants.SCAN_TYPE_SOCKET.
• Adds SCAN_TYPE_SOCKET and SCAN_TYPE_SOCKET_TIER1 constants in constants.mts and exports them.
• Version bump to 1.1.53 with CHANGELOG entry documenting the new scan_type behavior.

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