node_console_info now returns token_sha256_prefix (sha256, first 8 hex
chars) and token_ttl_seconds alongside the console WebSocket URL, and
controller WebSocket auth rejections include the sha256 prefix of the
token as received. Comparing the two immediately distinguishes a token
corrupted in transfer from server-side rejection causes (expired,
revoked, bad signature).
get_token_data used to raise the same "Could not validate credentials"
for every JWT-level failure (bad signature, expired, malformed), which
made console WebSocket auth failures impossible to tell apart. Return a
distinct detail per cause and log the underlying exception plus the
unverified header alg value on rejection.
