Brandling Safari: LAN safari-zone creature catching on the HD-2D engine

- Authoritative 30 Hz server (ENet, SQLite): accounts, characters, wild AI, tall grass /
  water / wandering spawns, fishing, captures, follower chains, clock + weather, LAN beacon
- Client: title / join / character creator / play screens, prediction + reconciliation,
  interpolated players and parties, HD-2D UI (dialogue with Professor Henry, HUD, collection)
- Shared deterministic zone generator, movement, protocol, roster, appearance
- Paper-doll character art pipeline (PixelLab base walk + per-item animation edits)
- Brandling roster from the company list (logo colors, jev types), Blender safari props
- Headless test bot

client/Common.h

@@ -0,0 +1,61 @@
+#pragma once
+// Small client-wide helpers: asset paths, UI textures, color conversion.
+
+#include "hd2d/GL.h"
+#include "hd2d/Texture.h"
+
+#include <imgui.h>
+
+#include <glm/glm.hpp>
+
+#include <cstdint>
+#include <string>
+
+#ifndef BS_ASSET_DIR
+#define BS_ASSET_DIR "assets"
+#endif
+#ifndef HD2D_ENGINE_ASSET_DIR
+#define HD2D_ENGINE_ASSET_DIR "../Vibe-HD-2D/assets"
+#endif
+
+namespace bs {
+
+inline std::string gameAsset(const std::string& rel) { return std::string(BS_ASSET_DIR) + "/" + rel; }
+inline std::string engineAsset(const std::string& rel) { return std::string(HD2D_ENGINE_ASSET_DIR) + "/" + rel; }
+
+constexpr float kPixelsPerUnit = 32.0f;     // world texel density shared by all pixel art
+constexpr float kCreaturePixelsPerUnit = 40.0f;  // creatures render a bit smaller than trainers
+
+inline ImU32 imColor(uint32_t rgb, int alpha = 255) {
+    return IM_COL32((rgb >> 16) & 255, (rgb >> 8) & 255, rgb & 255, alpha);
+}
+inline glm::vec3 linearColor(uint32_t rgb) {
+    auto f = [](uint32_t c) { float v = float(c & 255) / 255.0f; return v * v * (0.8f + 0.2f * v); };
+    return {f(rgb >> 16), f(rgb >> 8), f(rgb)};
+}
+
+// Plain RGBA8 (not sRGB), nearest-filtered texture for ImGui images: pixel art
+// previews and icons stay crisp and show their authored colors.
+class UiTexture {
+public:
+    UiTexture() = default;
+    UiTexture(const UiTexture&) = delete;
+    UiTexture& operator=(const UiTexture&) = delete;
+    ~UiTexture() { reset(); }
+    // `img` uses the engine convention (row 0 = bottom); ImGui uv (0,0) is the top-left.
+    void upload(const hd2d::Image& img);
+    void reset();
+    ImTextureID id() const { return ImTextureID(intptr_t(id_)); }
+    bool valid() const { return id_ != 0; }
+    glm::ivec2 size() const { return size_; }
+    // ImGui uv rect of a grid cell (top-left origin, rows counted from the top).
+    void cellUV(glm::ivec2 cell, int col, int row, ImVec2& uv0, ImVec2& uv1) const;
+
+private:
+    GLuint id_ = 0;
+    glm::ivec2 size_{0};
+};
+
+float wrapAngle(float a);  // to (-pi, pi]
+
+}  // namespace bs