Compute the insider key: HMAC-SHA256(apiKey, "insider"), truncated to 32 hex characters.
HMAC-SHA256(apiKey, "insider")
The server's API key (HMAC secret).
A 32-character lower-case hex key.
An insider key is path-independent: it grants full navigation for any path, unlike computePathKey or computeOutsiderKeyWithExpiry.
Compute the insider key:
HMAC-SHA256(apiKey, "insider"), truncated to 32 hex characters.