First-run onboarding: contextual coach-marks + How-to-Play card + dev replay toggle

Teaches the deep, interlocking loop — especially the inverted win condition
(you win by CLEARING EXPEDITIONS, not by surviving base sieges; DR-042/DR-043).

- OnboardingSystem: client-only observe-only PresentationSystemGroup overlay
  (own UIDocument @ sortingOrder 60), soft-gated 10-beat coach-mark sequence
  with a world-space ▶ pointer; never mutates sim / never destroys a ghost.
- OnboardingStepMath: pure, unit-tested step machine (snapshot + IsSatisfied +
  scheme-aware prompts + pointer kinds + persisted-mask helpers).
- HowToPlayPanel: tabbed reference card (Controls / The Loop / Build / Threats /
  Win-Lose), reachable from the main menu and the pause overlay.
- Per-client client-local state in GameSettings (TutorialHints + OnboardingMask
  bitmask, additive) — a Join client keeps its own; a host save-wipe never
  re-teaches. Settings toggle + menu "Replay Tutorial".
- Dev "Force Each Launch" toggle (GameSettings.ForceOnboardingEachLaunch):
  SettingsService.Boot wipes the mask + forces hints on in-memory every launch
  so the tutorial always replays fresh.
- HudSystem suppresses its own location hint while onboarding is active
  (single prompt voice), via OnboardingState + [UpdateAfter(OnboardingSystem)].

Validated green: 20/20 EditMode; Play smoke confirmed overlay render, clean
U+25B6 pointer glyph, no system sort-cycle, and the force-wipe end-to-end.

Docs: DR-043 + session log; reusable lesson archived in the build-gotchas note.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Assets/_Project/Scripts/Client/Presentation/HudSystem.cs

@@ -22,6 +22,7 @@ namespace ProjectM.Client
     /// </summary>
     [WorldSystemFilter(WorldSystemFilterFlags.ClientSimulation)]
     [UpdateInGroup(typeof(PresentationSystemGroup))]
+    [UpdateAfter(typeof(OnboardingSystem))] // read OnboardingState.Active same-frame (single prompt voice)
     public partial class HudSystem : SystemBase
     {
         // ---- palette (Aether language; Synty white skins are tinted into these) ----
@@ -290,6 +291,9 @@ namespace ProjectM.Client
                 _locationText.text = "BASE OVERRUN   -   resources lost; the Core will recover";
                 _locationText.style.color = new Color(1f, 0.3f, 0.25f);
             }
+            // First-run onboarding owns the prompt voice: while a coach-mark step is showing, blank the HUD's own
+            // location/gate hint so the player sees a single prompt (OnboardingSystem drives its own overlay).
+            if (OnboardingState.Active) _locationText.text = "";
             // ---- END-2: terminal run banner (Victory / Loss), observed from the replicated RunOutcome ----
             if (SystemAPI.TryGetSingleton<RunOutcome>(out var runOutcome) && runOutcome.Value != RunOutcomeId.InProgress)
             {