Apply better port list handling

[PropGit]

Wi-Fi ports tend to appear/disappear often (with current Wi-Fi discovery protocol) and are subject to less frequent but still possible appear/disappear behavior with increased network congestion (even with a better discovery protocol).

Consider easy ways to make the list more stable so that BlockyProp users don't end up with so many opportunities for their selected port to 1) change*, or 2) disappear momentarily.

*The selected port tends to change right after the user selects one if the browser is waiting for a get_ports() response and the returned list contains at least one additional or one fewer entry.

[PropGit]

After consideration, it's best to solve this problem the way it should have been solved in the first place - by implementing a hearty discovery protocol in the Wi-Fi Module + PropLoader.
See next post

[PropGit]

Reconsidering - Turns out, if this is implemented as a short-term history filter, it plays an important role in solving Issue #86 as well.

Algorithm (to be combined with that from Issue #86):

• A history list is created for wireless ports (a list of recently discovered ports)
  • Contains same Name, IP, MAC fields returned by PropLoader with the addition of UID and Life fields
    • UID = Name (+ possibly '-#') where # is one or more ending digits from the MAC address, making the UID a unique form of Name. This field is filled in by code from Issue Prevent duplicates in port list #86.
• Each successful wireless port retrieval process will compare newly retrieved items to that of the history list
• The history list is extended to include non-duplicates
  • A new item found to have an old item's MAC address results in an updated element
    • Updated IP
    • If new Name matches old Name then Name and UID fields are left as-is
    • If new Name is different than old Name, the old Name is updated to New Name and UID is updated accordingly (Issue Prevent duplicates in port list #86).
    • Life field is set to 4
  • A new item found not to match any old item's MAC address results in a new item
    • Name, IP, and MAC is set to item's details
    • UID is set according to Issue Prevent duplicates in port list #86
    • Life field is set to 4
• The history list is potentially trimmed by
  • Subtracting 1 from each element's Life field and removing each item with a Life value of 0

The UID of each list item is returned as the wireless port identifier.
Requests to download and/or debug via a wireless port identifier searches the UID of the history list for a match.

In this way, the wireless ports in the port list will update as soon as a new port is found, will retain recently-found ports for longer (with up to two contiguous refresh requests missing a particular wireless port identifier), lessening the occurrence of a momentary wireless port disappearance from the port list, and will present newly discovered modules with a duplicate identifier as unique identifiers for that session; solving the name-to-ip resolution issue.

[PropGit]

Implemented, tested, and merged via PR #96.

See final algorithm in last post of Issue #86.