docs(test): clarify Loader integer-key enumeration

JavaScript object enumeration moves canonical array-index property keys ahead
of other string keys. Describing every numeric-looking Loader ID as reordered
is too broad: leading-zero and other noncanonical numeric strings remain
ordinary string properties.

Name the exact key category in the inventory fixture's local comment. The
inventory-* IDs exclude every canonical array-index key, and the real Loader
activation, fixture order, output assertions, and production code are unchanged.
This addresses the automatic review's nonblocking terminology clarification.

Validation:
- Type-aware Oxlint passed for the owning inventory.spec.ts.
- git diff --check passed.
- No behavior or test inputs changed, so the already observed 46-test and
  74/74-branch evidence remains applicable.

packages/llm/plugin-package-inventory-deepseek/tests/inventory.spec.ts

@@ -103,7 +103,7 @@ describe('DeepSeek plugin package inventory', () => {
     const versioned = await packagePlugin(root, 'versioned', { name: 'same', version: 'undefined' })
     const unversioned = await packagePlugin(root, 'unversioned', { name: 'same' })
     const entries = reversed ? [unversioned, versioned] : [versioned, unversioned]
-    // Numeric generated IDs precede other keys in Loader's object-backed store.
+    // Canonical array-index IDs precede other keys in Loader's object-backed store.
     // Named IDs preserve both requested arrival orders before inventory sorting.
     await ctx.loader.root.update([...entries, ...entries].map((name, index) => ({
       id: `inventory-${String(index)}`,