Increase all BGAN TRAIT minimum runtimes to 7 days (168 hours)

The current BGAN TRAIT CONSTITUTION allows for a range of minimum runtimes depending on the kind of proposal. I think all of these minimum runtimes should be extended out to 7 days or 168 hours. This update would have zero cost to the community because fast proposals in the realm of traits offer no real upside. If anything, longer time frames allow for more people to check in less frequently while still getting a chance to particpate in trait governance. Overall, I think this change will increase the quality of the results of trait-specific proposals.

If this proposal passes the minimum runtime for the following will all be updated to 7 days or 168 hours.

Criteria modification proposal (currently 3 days or 72 hours) Classification amendment proposals (currently 2 days or 48 hours) Constitutional amendment proposals (currently 5 days or 120 hours) Veto proposal (currently 2 days or 48 hours) Locking & unlocking metadata property proposals (currently 3 days or 72 hours)