feat(install): ask for the public URL, wire it into .env

install.sh now asks one question on fresh installs — the URL the app is
opened on. Accepts https://primora.example.com (TLS at the user's proxy),
primora.example.com, or 192.168.1.50:8085; the port becomes NGINX_PORT.
The answer rewrites every public URL var and COOKIE_DOMAIN for real DNS
names. PUBLIC_URL env keeps it non-interactive; legacy DOMAIN/NGINX_PORT
still work; reruns over an existing .env skip the question and display
the URL from the file.

Also trust both URL schemes on the serving host in trustedOrigins —
external TLS termination makes nginx report http while browsers arrive
over https.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to Primora. Format follows [Keep a Changelog](https://keepac
 
 ## [Unreleased]
 
+### Added
+
+- **Install script asks for the public URL** — `install.sh` now prompts for where you'll open the app and accepts a full URL: `https://primora.example.com` (TLS at your proxy, hints printed at the end), `primora.example.com`, or `192.168.1.50:8085` (the port becomes `NGINX_PORT`). The answer rewrites every public URL var in `.env` and `COOKIE_DOMAIN` for real DNS names. Non-interactive via `PUBLIC_URL=`; legacy `DOMAIN`/`NGINX_PORT` envs still work; reruns over an existing `.env` skip the question.
+
 ## [0.8.2] - 2026-09-28
 
 ### Fixed