## Summary
Migrates 14 ConPVP lobby/tournament gumps from legacy `Gump` to modern `DynamicGump`/`StaticGump<T>`. Layouts move into `BuildLayout(ref DynamicGumpBuilder)`, constructors become private, and validation moves into static `DisplayTo` entry points (empty-gump rule).
**Per-gump base type decisions:**
- `BeginGump` → `StaticGump<BeginGump>`: layout is fully fixed (no dynamic content). All other gumps below are `DynamicGump` because they bake dynamic player names, guild abbreviations, ruleset titles, arena names, tournament participant names, ladder rankings, or per-instance rule modifications. Per the cliloc/dynamic-text rule, dynamic content forces `DynamicGump`.
- `ReadyGump`, `ReadyUpGump` → `DynamicGump` (per-instance participant rosters).
- `AcceptDuelGump`, `AcceptTeamGump`, `ConfirmSignupGump` → `DynamicGump` (challenger/registrar/team names, dynamic rule modifications).
- `PickRulesetGump`, `RulesetGump` → `DynamicGump` (ruleset titles and option labels per instance).
- `ParticipantGump`, `DuelContextGump` → `DynamicGump` (player rosters/team labels).
- `LadderGump` → `DynamicGump` (ladder entries: ranks, levels, guild abbrs, names, wins/losses).
- `ArenaGump` → `DynamicGump` (arena names with active player names).
- `PreferencesGump` → `DynamicGump` (arena name list).
- `TournamentBracketGump` (~1k LOC) → `DynamicGump`. The whole gump is one type-switched view that re-renders on every button press across `Index`, `Rules_Info`, `Participant_List`, `Participant_Info`, `Round_List`, `Round_Info`, `Match_Info`, `Player_Info`. All branches bake per-instance content.
**Refresh-via-this conversions (the big perf wins):**
- `LadderGump`: page +/- now mutates `_page` and calls `from.SendGump(this)` instead of allocating a new `LadderGump`.
- `PickRulesetGump`: ruleset apply / flavor toggle now refreshes via `this`.
- `ParticipantGump`: increase/decrease team size, remove player, target failure all refresh via `this`.
- `DuelContextGump`: failed-start and add-participant refresh via `this`.
- `ConfirmSignupGump`: every signup-validation rejection branch in `OnResponse` and every `AddPlayer_OnTarget` rejection branch refreshes via `this` (was allocating a new gump per branch).
- `TournamentBracketGump`: every navigation button (back/forward, type change, page change, drill-down) mutates `_type`/`_object`/`_list`/`_page` and refreshes via `this`. Previously each click allocated a new 1k LOC gump.
All gumps are `Singleton`, use private constructors with static `DisplayTo` entry points that null-check `NetState` before allocation. External callers in `DuelContext`, `TournamentBracketItem`, `TournamentController`, `TournamentSignupItem`, and the cross-references between `AcceptDuelGump`/`ParticipantGump`/`AcceptTeamGump`/`ConfirmSignupGump` are all updated to use `DisplayTo`. Legacy `m_X` fields renamed to `_x` per coding standards.
