fix(standards): bound transfer policy dispatch to the reference block

[onurinanc]

Summary

• Apply the default expiration limit in invoke_transfer_policy, before the pause check, so the pause flag and every active policy are bounded to the reference block.
• Document the limit on invoke_send_policy, invoke_receive_policy, TransferAllowAll and TokenPolicyManager.

Closes #3744.

[partylikeits1983]

Was this not addressed already here? #3512

[onurinanc]

@partylikeits1983

After #3512 is merged I believe the following are still left:

• The active policy root itself is read by the dispatcher before the dispatch happens, which means that switching from an allow_all policy to a more restrictive policy could be indefinitely bypassed by anchoring to a reference block that existed before the switch.
• The pause flag is read by the dispatcher rather than by the policy itself, so it was only incidentally limited whenever the active policy happened to set its own limit
• Policy roots that were registered using TransferPolicy::custom were not enforced
• An active TransferAllowAll policy does not set any expiration date, and the dispatcher does not set one either, which is why these transfers remained unbounded and limitless.

So, I've done this updates to fully close #3744