Add production-like local Docker edge stack for docs + API

[Logiar]

Summary

• add a distroless docs container image (web/Dockerfile) with a lightweight static server (web/server.mjs) for Astro build output
• add a production-like local topology in docker-compose.yml with an edge nginx service routing example.com to docs and api.example.com to the API
• add docker/nginx/local-edge.conf plus README guidance for hosts mapping and explicitly documented local-dev allowances (localhost:3000, localhost:8080, and /api/* fallback)

Test Plan

• docker compose config
• docker compose build docs api
• docker compose up -d then curl -H 'Host: example.com' http://127.0.0.1/ returns docs HTML
• docker compose up -d then curl -H 'Host: api.example.com' 'http://127.0.0.1/now?format=iso' returns timestamp
• CORS preflight check on api.example.com returns 204 with allow-origin header for http://example.com

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Permit localhost origin for edge-served docs

The CORS map allows http://localhost:3000 but not http://localhost, even though this same file defines a server_name localhost edge route for docs. When users open docs via http://localhost and the UI calls http://api.example.com, the browser sends Origin: http://localhost; that falls through to default "", so Access-Control-Allow-Origin is empty and the request is blocked by CORS. Adding http://localhost to the map avoids breaking the localhost edge workflow.

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[Logiar]

Fixed in a06c844. Added http://localhost to the CORS origin map so the localhost edge workflow (Host: localhost docs -> api.example.com) returns a valid Access-Control-Allow-Origin header. Also re-ran a preflight check with Origin: http://localhost and it now returns 204 with the expected CORS header.