feat: launch 3d architecture documentation portal

engineering/development-setup.md

@@ -0,0 +1,10 @@
+---
+title: "Development Setup"
+description: "Prepare a contributor environment when application code becomes available."
+---
+
+# Set up the project
+
+Clone the application repository with the approved SSH identity, inspect its project scripts, and use the committed pnpm version. Do not infer commands that are not yet present.
+
+For this documentation portal, run `pnpm install --frozen-lockfile` followed by `pnpm validate`.

engineering/overview.md

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+---
+title: "Engineering Overview"
+description: "Use the engineering boundary to prepare implementation work."
+slug: /
+---
+
+# Prepare implementation
+
+The application repository is [corp-v1-3darch](https://gitea.lego-cloud.eu/corp-v1-3darch/corp-v1-3darch). This portal documents product and engineering direction while implementation lives with the application.
+
+Prefer TypeScript, pnpm, testable model adapters, and browser-level behavior checks for the POC.