Clarify EIP-6372 clock bounds

Author: immrsd

content/contracts-cairo/3.x/api/governance.mdx

@@ -185,6 +185,10 @@ Whether a proposal needs to be queued before execution. This indicates if the pr
 Delay between when a proposal is created and when the vote starts. The unit this duration is expressed in depends on the clock (see [ERC-6372](https://eips.ethereum.org/EIPS/eip-6372)) this contract uses.
 
 This can be increased to leave time for users to buy voting power, or delegate it, before the voting of a proposal starts.
+
+NOTE: While this function returns a u64 value, timepoints must fit into u48 according to
+the EIP-6372 specification. Consequently this value must fit in a u48 (when added to the
+current clock).
 </APIItem>
 
 <APIItem

content/contracts-cairo/3.x/api/utilities.mdx

@@ -275,6 +275,9 @@ Returns the current timepoint determined by the contract's operational mode, int
 Requirements:
 
 - This function MUST always be non-decreasing.
+
+NOTE: While this function returns a u64 value, timepoints must fit into u48 according to
+the EIP-6372 specification.
 </APIItem>
 
 <APIItem