feedback5 R5: split the field-view helpers out of the render app

PIXI loading, pick records, tunables, view kind, unit info and the asset / GL
host now live in public/js/render/app/*.js. createFieldView stays in app.js,
unchanged, and every name the file used to export is re-exported. One
pixiPromise. Two source pins follow the lines that moved.

public/js/render/app/host.js

@@ -0,0 +1,66 @@
+// public/js/render/app/host.js — asset lookup, data lookup and GL teardown for one field view.
+
+import { createAssets, assets as defaultAssets } from '../../assets.js';
+
+function withTimeout(p, ms) {
+  return Promise.race([p, new Promise((resolve) => setTimeout(resolve, ms))]);
+}
+
+/** Wrap whatever the caller passed as `assets` into the store API of public/js/assets.js. */
+function resolveAssets(a) {
+  if (a && typeof a === 'object' && typeof a.ready === 'function' && typeof a.spineEntry === 'function') return a;
+  if (a && typeof a === 'object' && (a.chars || a.enemies || a.version)) return createAssets({ manifest: a });
+  return defaultAssets;
+}
+
+function makeData(src) {
+  const look = (file, id) => {
+    if (id == null || id === '') return null;
+    try {
+      if (src && typeof src.lookup === 'function') return src.lookup(file, id) || null;
+      const m = src && src[file];
+      if (m instanceof Map) return m.get(id) || null;
+      if (m && typeof m === 'object' && Object.hasOwn(m, id)) return m[id] || null;
+    } catch { /* ignore */ }
+    return null;
+  };
+  return {
+    chess: (id) => look('chess', id), token: (id) => look('tokens', id), item: (id) => look('items', id),
+    enemy: (id) => look('enemies', id), stage: (id) => look('stages', id), bond: (id) => look('bonds', id),
+  };
+}
+
+const QUALITY_RES = { high: 2, medium: 1.5, low: 1 };
+
+/** Pixel-ratio cap of the 3D board canvas per quality (its fill cost is the PBR board, not the sprites). */
+const BOARD_RES = { high: 2, medium: 1.25, low: 1 };
+
+/**
+ * Before a renderer is destroyed: free its GL copies of every texture / buffer / geometry / framebuffer it
+ * uploaded. Module-level textures (FX atlas, tier chips, backdrop, diamonds, Spine pages, PIXI.Texture.WHITE…)
+ * outlive the view; PIXI 7 leaves their per-context GL entries and 'dispose' listeners pointing at the dead
+ * renderer, which kept every unmounted view's renderer, canvas and WebGL context reachable.
+ */
+export function releaseGl(renderer) {
+  const ts = renderer && renderer.texture;
+  if (ts && Array.isArray(ts.managedTextures) && typeof ts.destroyTexture === 'function') {
+    for (const bt of ts.managedTextures.slice()) { try { ts.destroyTexture(bt, true); } catch { /* ignore */ } }
+    ts.managedTextures.length = 0;
+  }
+  for (const sys of [renderer?.geometry, renderer?.buffer, renderer?.framebuffer]) {
+    try { if (sys && typeof sys.disposeAll === 'function') sys.disposeAll(false); } catch { /* ignore */ }
+  }
+  // shader programs are cached globally by source (PIXI.utils.ProgramCache) with one GLProgram per context
+  const uid = renderer?.CONTEXT_UID, gl = renderer?.gl;
+  const programs = globalThis.PIXI?.utils?.ProgramCache;
+  if (uid != null && programs && typeof programs === 'object') {
+    for (const prog of Object.values(programs)) {
+      const g = prog && prog.glPrograms && prog.glPrograms[uid];
+      if (!g) continue;
+      try { if (gl && g.program) gl.deleteProgram(g.program); } catch { /* ignore */ }
+      delete prog.glPrograms[uid];
+    }
+  }
+}
+
+export { withTimeout, resolveAssets, makeData, QUALITY_RES, BOARD_RES };