Adding code examples to the Navara docs

First read .claude/skills/navara-usage/SKILL.md (and the reference matching the topic) so the snippet demonstrates correct, idiomatic API usage. The authoritative process docs live in the repo — read them before writing:

• docs/AGENTS.md — entry point and key principles
• docs/guide/WRITING_RULES.md — terminology and link rules
• docs/guide/NAVARA_THREE_INSTRUCTIONS.md — update workflow, package→section map, WASM .d.ts handling
• docs/guide/NAVARA_THREE_UPDATE_CHECKLIST.md — scenario checklists
• docs/guide/TRANSLATION_GUIDE.md — when touching ja/

Non-negotiable principles

1. The code is the source of truth — match the implementation exactly. Types, parameter names, return values, and defaults in a snippet must match the TypeScript source (verify by reading the actual exports/JSDoc, never guess). Material/WASM types are documented in their normalized shape (plain optional properties via NormalizeWASMClass), not the raw WASM class with free()/getters — extract from the getters in web/wasm/**/*.d.ts.
2. English first. Root locale is English and is the source of truth; ja/ mirrors the structure. Write/update English, then mirror to ja/ (technical terms and API names stay in English in every locale).
3. Examples must be complete and runnable — include imports and required setup (e.g. await view.init() before addLayer), not fragments that would throw if pasted.
4. Snippets must respect API invariants — e.g. never show addPlugin after init(), never show writes to camera.raw.fov, show Layer.update() with a full config. See the gotcha list in navara-usage.

Where docs live