fix: correct 2023-03-21 client wire contracts across the API and notify surfaces

Audits every route the March-2023 client can call against what this server
actually serves, and fixes the defects that were breaking gameplay. Adds
docs/recroom-2023-client-api-complete.md as the reference: ~500 route
literals across 13 subsystems, with verb, request/response shape, and a
per-subsystem diff. 315 defects catalogued; the ones fixed here are listed
in its "Already fixed" table.

Path coverage was never the problem — 465 of 506 routes already had
handlers. The failures were in shape, and they cluster into four causes:

- Wrong verb. The verb is a BestHTTP.HTTPMethods ordinal (GET=0 .. PATCH=5),
  confirmed from that enum's static constructor. Routes registered POST-only
  while the client PUTs returned 405, which made room consumables neither
  buyable nor consumable and blocked every room-key edit.
- Bare scalar wrapped in an object. The client reads `1000`, not
  `{"Limit":1000}`; the issuing method signature says which. Wrapping makes
  the deserializer throw and the feature dies silently.
- [FromBody] vs form-urlencoded. The client sends nearly every write as form
  data, which an [ApiController] action bound [FromBody] rejects with 415
  before the handler runs. This alone broke all 13 club member-management
  endpoints. Adds Binding/FormOrJsonModelBinder so this is fixed once.
- Notify dispatch keys. Both enum overloads of the client's RegisterHandler
  lower the id via Int32.ToString() and register only that numeric key, and
  lookup is a case-sensitive TryGetValue that returns silently on a miss. We
  were sending the enum NAME for most ids, so friend-request updates, forced
  logout, maintenance broadcasts, live balance and consumable updates, and
  invention moderation pushes all evaporated with no error anywhere.

Notable behavioural bugs fixed:

- Editing a club announcement deleted it: PUT was a third binding on the
  delete handler. Split apart, and the missing create route added.
- leaderboard/CheckAndSetStat did not exist. The 2023 client has no SetStat
  literal at all, so every leaderboard score it wrote was discarded.
- Setting a club clubhouse cleared it: the handler read roomId from the query
  while the client sends it in the body, then wrote the resulting null.
- Club join requests were inverted (the enum is Open=0, InviteOnly=1,
  AskToJoin=2), so ask-to-join clubs rejected everyone and invite-only clubs
  quietly admitted them.
- Room bans were pushed as id 24, for which the client registers no handler;
  they now go out as ModerationKick with IsBan, so the ban takes effect
  immediately instead of at next login.
- Room-key ownership queries answered for the wrong player, and "has anyone
  bought this key" asked "did I buy it" — always false for the creator.

Also persists settings that were previously acknowledged and dropped
(playlist accessibility/restrictions/level-voting/warning, per-player status
visibility, VR movement mode and avoid-juniors, custom room codes), which is
what the new columns in the migration are for.

One test asserted the old nested PriceAndCurrency response shape; the
client's consumable formatter has no such key and reads Price and
PurchaseCurrencyId flat, so the test was corrected alongside the handler.

DorkNet.Server/Controllers/API/UgcPurchasables/UgcPurchasablesController.cs

@@ -11,9 +11,17 @@ namespace DorkNet.Server.Controllers.API.UgcPurchasables;
 [ApiController]
 public class UgcPurchasablesController(DorkNetDbContext db) : ControllerBase
 {
+    /// <summary>The 2023-03-21 client asks for a room's in-room store with the
+    /// path form <c>api/ugcPurchasables/v1/items/room/{roomId}</c>, not the
+    /// <c>?roomId=</c> query this handler was originally written for. Without
+    /// the path route it 404'd and the in-room UGC store never populated on
+    /// room join.</summary>
+    [HttpGet("api/ugcPurchasables/v1/items/room/{roomId:long}")]
     [HttpGet("api/ugcPurchasables")]
     [AllowAnonymous]
-    public async Task<IActionResult> List([FromQuery] long roomId = 0)
+    // No explicit binding source: roomId comes from the route on the path form
+    // above and from the query string on the bare route.
+    public async Task<IActionResult> List(long roomId = 0)
     {
         var rows = await db.UgcPurchasables
             .Where(i => !i.IsDeleted && (roomId <= 0 || i.RoomId == roomId))