piha.lc / beta.piha.li + company_site marketing landing (#4)

## Summary

- Public short domain is **`piha.lc`** (prod) and **`beta.piha.li`** (beta)
- `/` is a marketing page in [aimloperations.com](https://aimloperations.com) / `company_site` styling (Inter, dark, cyan)
- CTA: want access → [contact](https://aimloperations.com/contact)
- Nav/logo/footer match the company site; debug mint form uses the same chrome

Closes #3.

## Secrets (control node)

Update hostnames only — no new token/pepper unless you are rotating:

**`url_shortening_service_prod.env`**
```text
DJANGO_ALLOWED_HOSTS=piha.lc,shortener.aimloperations.com,url-shortener,web
SHORT_DOMAIN=piha.lc
PUBLIC_SHORT_URL=https://piha.lc
SHORT_PUBLIC_HOSTS=piha.lc
CONTACT_URL=https://aimloperations.com/contact
```

**`url_shortening_service_beta.env`**
```text
DJANGO_ALLOWED_HOSTS=beta.piha.li,shortener-beta.aimloperations.com,url-shortener,web
SHORT_DOMAIN=beta.piha.li
PUBLIC_SHORT_URL=https://beta.piha.li
SHORT_PUBLIC_HOSTS=beta.piha.li
CONTACT_URL=https://aimloperations.com/contact
```

NPM: `piha.lc` / `beta.piha.li` → this container. Still do not proxy `/api/` on the short host.

## Test plan
- [ ] `cd site && uv run python manage.py test`
- [ ] `GET /` looks like aimloperations.com; Request access / Contact go to aimloperations.com/contact
- [ ] `GET /<code>` still 302
- [ ] `/api/` on Host `piha.lc` is 404

Reviewed-on: #4

.env.example

@@ -13,12 +13,13 @@ DJANGO_ALLOWED_HOSTS=localhost,127.0.0.1,0.0.0.0,web,url-shortener
 SITE_NAME=URL Shortening Service
 CREDIT_NAME=AI ML Operations
 CREDIT_URL=https://aimloperations.com
+CONTACT_URL=https://aimloperations.com/contact
 
 SHORT_DOMAIN=localhost:8005
 # Origin printed in minted short_url (phones hit this). Local: this machine.
 PUBLIC_SHORT_URL=http://127.0.0.1:8005
 # Host values that only serve GET /<code> (no /api/).
-SHORT_PUBLIC_HOSTS=go.mkdrealtor.com
+SHORT_PUBLIC_HOSTS=piha.lc
 # Host values that serve /api/ (Bearer required). May include a public DNS name.
 SHORT_API_HOSTS=localhost,127.0.0.1,0.0.0.0,web,url-shortener
 # Django admin — keep local. Do not add the public API hostname.