Describe the live Studio inspector in its README

The model paragraph now lists the edit decisions the model owns (key
refusal by bytes and by the dictionary comparer, fresh keys, element
choices, integer clamping) and names CreateInspectorModel. The drawer
section states the return-and-GUI.changed contract and the discarded
frame on a throw. The sample drawer draws a hex color string instead of
CultMath.float3, which the package no longer references.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/GameCult.Unity/Assets/Caching/README.md

@@ -39,19 +39,22 @@ reloading scripts drops unsaved edits.
 ## Inspection Model
 
 `CultInspectorModel` is engine-free and lives beside the inspector attributes
-in `GameCult.Caching`. Given a registry and the store's document codec it gives
-the member list of a type (registry catalog slots, `CultInspector*` metadata,
-whether a member is assignable), the shape of any value (string, integer,
-float, bool, enum, `CultRecordRef<T>` with its candidate records, rank-1 list
-or array, dictionary, `[Union]` with only its declared subtypes, nested keyed
-object, struct edited in place through its public fields, or unsupported with
-a reason), drawer claim resolution
-(`CultInspectorDrawerClaims`), dictionary key identity and refusal (null keys,
-empty record references and duplicates), and edits that work on a copy
-(`CultInspectorEdit`): a refused upsert leaves the cached object unchanged. The
-Studio is one lowering of that model and owns only widgets and layout; a
-runtime CultUI panel needs only its own renderer and drawers to show and edit
-the same documents under the same rules.
+in `GameCult.Caching`; `CultCacheMessagePack.CreateInspectorModel` builds it
+over a `.cc` store's codec. It gives the member list of a type (registry
+catalog slots, `CultInspector*` metadata, whether a member is assignable), the
+shape of any value (string, integer, float, bool, enum, `CultRecordRef<T>` with
+its candidate records, rank-1 list or array, dictionary, `[Union]` with only
+its declared subtypes, nested keyed object, struct edited in place through its
+public fields, or unsupported with a reason), drawer claim resolution
+(`CultInspectorDrawerClaims`), and the edit decisions: the key a dictionary
+entry keeps and the notice when a key is refused (null, an empty record
+reference, or a duplicate: serialized the same as another key or equal by the
+dictionary's own comparer), the fresh key an added entry gets, what a new list
+element, dictionary value or union pick may be, and how an integer edit clamps
+to its type. Edits work on a copy (`CultInspectorEdit`): a refused upsert
+leaves the cached object unchanged. The Studio is one lowering of that model
+and owns only widgets and layout; a runtime CultUI panel needs only its own
+renderer and drawers to show and edit the same documents under the same rules.
 
 ## Drawers
 
@@ -66,8 +69,13 @@ A project adds or overrides a drawer with an editor class. `Claimed` is either
 a value type (an open generic definition claims every closed form) or an
 attribute type, which claims every member carrying it. Attribute claims win
 over type claims, which win over built-in drawing. A claim two drawers make is
-used by neither: both are logged and the member shows the error row. A drawer
-that throws draws an error row and leaves the value unchanged.
+used by neither: both are logged and the member shows the error row.
+
+A drawer returns the new value and lets its IMGUI controls set `GUI.changed`;
+only a frame that reports a change is saved. Mutating the value in place
+without reporting a change is not saved reliably. A drawer that throws shows
+an error row and discards that frame's edit copy, so nothing edited in that
+frame is saved.
 
 ```csharp
 using System;
@@ -77,20 +85,22 @@ using GameCult.Unity.Caching.Editor;
 using UnityEditor;
 using UnityEngine;
 
+// Lives beside the documents; an attribute needs no Unity reference.
 public sealed class ColorAttribute : Attribute
 {
 }
 
+// Draws a "#RRGGBBAA" string member as a color field.
 [CultInspectorDrawer(typeof(ColorAttribute))]
 public sealed class ColorDrawer : ICultInspectorDrawer
 {
     public object Draw(CultInspector inspector, string label, Type type, object value, MemberInfo member)
     {
-        if (type != typeof(CultMath.float3))
+        if (type != typeof(string))
             return inspector.DrawDefault(label, type, value, member);
-        var v = (CultMath.float3)value;
-        var c = EditorGUILayout.ColorField(label, new Color(v.x, v.y, v.z));
-        return new CultMath.float3(c.r, c.g, c.b);
+        ColorUtility.TryParseHtmlString(value as string ?? string.Empty, out var color);
+        var next = EditorGUILayout.ColorField(label, color);
+        return next == color ? value : "#" + ColorUtility.ToHtmlStringRGBA(next);
     }
 }
 ```