Document live node kind previews

[konojunya]

Background

The built-in cache visual and dense-layout routing have been approved and released through Theme 0.7.0, Engine 0.9.0, and Stack CLI 0.5.3. Users also need to see every semantic node kind as the current renderer actually draws it, rather than infer shape from prose or stale SVG assets.

Implementation Approach

• Add a live NodeKindCatalog mount to the Node Kinds reference in English, Japanese, Chinese, and Korean.
• Explain that kind is semantic while the active theme owns shape, palette, and fallback icon, including custom theme overrides.
• Keep Engine references version-agnostic in prose because the UI reports the exact pinned runtime version.
• Pin Docs validation to @stack-sh/engine 0.9.0 and synchronize all generated install/agent guidance to the immutable Stack CLI 0.5.3 release.

Testing Approach

• Deterministic generation check and 22 source/generator/locale tests.
• Machine resource validation across 64 hashes, 25 diagnostics, nine examples, 13 diagnostic fixtures, and four live WASM intelligence fixtures.
• Generated skill and first-render smoke in all four locales against the published Stack CLI 0.5.3 binary.
• Native compiler conformance and release/source integrity remain enforced by CI.

Review Perspectives / Points of Concern

• The catalog tag is a Web-owned live component; this repository remains the canonical multilingual prose and generated-content source.
• No SVG preview is stored here. Web renders every kind on-device with the pinned Engine/WASM package so future layout improvements appear after the runtime pin advances.
• Custom cylinder rendering remains supported by Theme/Engine; only built-in cache fallback visuals use the approved rounded card.