M4: Tactical render + unified seamless-zoom WorldView

Implements the seamless-zoom contract from CLAUDE.md: one Camera2D
covers both world-map and tactical scales; layers fade in/out at zoom
thresholds; polyline widths and the player marker counter-scale with
zoom so on-screen sizing stays consistent across the full range.

Layers (bottom-up in WorldView):
  Biome sprite     — 256x256 ImageTexture scaled by WORLD_TILE_PIXELS;
                     always visible (acts as backdrop past the tactical
                     streaming radius).
  TacticalChunks   — TacticalChunkNode children added on chunk-loaded
                     event; visible only when zoom ≥ 4.
  Polylines/Bridge — Line2D children; always visible. Width recomputed
                     each frame as baseScreenPx / camera.Zoom so the
                     on-screen stroke is constant (4 px highway, 3 px
                     post road, 2 px dirt road, 4.5/3/2 for major-river/
                     river/stream, 4/2 for rail tie/line, 6 for bridge).
  Settlements      — SettlementDot children; hidden when zoom ≥ 2 (you
                     are visually "inside" them at tactical scale).
  PlayerMarker     — Always visible; Scale = 1/zoom keeps it at
                     PLAYER_MARKER_SCREEN_PX on-screen across all zooms.

TacticalAtlas:
  Loads PNGs from Content/Gfx/tactical/{surface,deco}/ via ContentLoader
  with name_0.png/name_1.png/... variant probing (silent miss). Falls
  back to procedurally-generated solid placeholders matching MonoGame's
  TacticalAtlas colour table so missing art doesn't break rendering.

TacticalChunkNode:
  One Node2D per cached chunk, positioned at (OriginX, OriginY) in
  world-pixel space. _Draw iterates the 64x64 tile grid once and Godot
  caches the rasterised CanvasItem; subsequent frames blit instead of
  re-issuing 4096 DrawTextureRect calls.

ChunkStreamer integration:
  WorldView listens to OnChunkLoaded / OnChunkEvicting and adds /
  removes TacticalChunkNode children. Streaming radius is computed
  dynamically from the viewport size and camera zoom plus a 2-tile
  buffer, so chunk loads always cover the visible viewport with margin.
  Chunks only stream when zoom ≥ 4 (tactical is visible).

Main.cs:
  --world-map [seed]            → WorldView, fit-to-viewport zoom
  --tactical  [seed] [tx] [ty]  → WorldView, zoom 32 at given tile
  Both flags converge on the same scene; mouse wheel transitions
  seamlessly between modes.

ContentLoader silent miss:
  Removed the "Missing texture" PrintErr — atlas variant probing
  legitimately tries name_3.png that doesn't exist, and the noise
  drowned the console. Genuine asset failures still surface via
  AssetTest's count summary.

Deleted (replaced by WorldView):
  Theriapolis.Godot/Rendering/WorldMapView.cs
  Theriapolis.Godot/Rendering/TacticalView.cs (created earlier in M4,
  never committed — superseded before commit).

Closes M4 of theriapolis-rpg-implementation-plan-godot-port.md.
Next: M5 (codex design system).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Theriapolis.Godot/Main.cs

@@ -20,6 +20,7 @@ public partial class Main : Node
         ulong? smokeTestSeed = null;
         ulong? worldMapSeed = null;
         bool runAssetTest = false;
+        (ulong seed, int tx, int ty)? tacticalArgs = null;
         for (int i = 0; i < args.Length; i++)
         {
             if (args[i] == "--smoke-test")
@@ -43,6 +44,19 @@ public partial class Main : Node
                 worldMapSeed = seed;
                 break;
             }
+            if (args[i] == "--tactical")
+            {
+                ulong seed = 12345UL;
+                int tx = 128, ty = 128;
+                if (i + 1 < args.Length && ulong.TryParse(args[i + 1], out var s))
+                    seed = s;
+                if (i + 2 < args.Length && int.TryParse(args[i + 2], out var x))
+                    tx = x;
+                if (i + 3 < args.Length && int.TryParse(args[i + 3], out var y))
+                    ty = y;
+                tacticalArgs = (seed, tx, ty);
+                break;
+            }
         }
 
         if (smokeTestSeed.HasValue)
@@ -61,10 +75,22 @@ public partial class Main : Node
 
         if (worldMapSeed.HasValue)
         {
-            // Replace the M0 hello-world children with the M2 world-map view.
+            // M4: unified seamless-zoom view. --world-map starts zoomed out
+            // (fit-to-viewport, initialZoom=0 = compute fit), --tactical
+            // starts at native sprite zoom 32 with the player at the given
+            // tile. Wheel between them seamlessly.
             foreach (Node child in GetChildren())
                 child.QueueFree();
-            AddChild(new WorldMapView(worldMapSeed.Value));
+            AddChild(new WorldView(worldMapSeed.Value));
+            return;
+        }
+
+        if (tacticalArgs.HasValue)
+        {
+            foreach (Node child in GetChildren())
+                child.QueueFree();
+            var (seed, tx, ty) = tacticalArgs.Value;
+            AddChild(new WorldView(seed, tx, ty, initialZoom: 32f));
             return;
         }