feat: console welcome with proksi.local + post-install reboot flow

Two user-visible polish passes on top of the walking-skeleton install:

- Console welcome: live ISO's getty no longer shows the bare Arch prompt.
  `/etc/hostname` is now `proksi` so avahi advertises `proksi.local`;
  a systemd oneshot (`furtka-issue.service`, runs after
  network-online.target) regenerates `/etc/issue` via
  `/usr/local/bin/furtka-update-issue` to show both
  `http://proksi.local:5000` (preferred, via mDNS — avahi and nss-mdns
  are already in `packages.extra`) and the raw IP as a fallback for
  networks where mDNS is flaky. `agetty --reload` nudges the already-
  running login prompt to redraw.

- /install/log now polls a JSON endpoint (`/install/log.json`) every
  3 s instead of meta-refresh, so expanding the collapsed log
  `<details>` doesn't get eaten by the refresh. Noscript fallback
  keeps the meta-refresh for JS-off users. When the install finishes,
  the Done state shows a Reboot-now button that POSTs to
  `/install/reboot` (guarded server-side to only reboot once status
  is "done", so a panicked click mid-pacstrap can't brick the box).
  A confirm() reminds the user to pull the USB / eject the ISO first.

End-to-end tested on a Proxmox VM 2026-04-14: boot → wizard →
archinstall → Done state → Reboot now → VM came back up → login as
created user → `docker ps` worked.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

iso/overlay/airootfs/etc/hostname

@@ -0,0 +1 @@
+proksi

iso/overlay/airootfs/etc/issue

@@ -0,0 +1,6 @@
+
+  Furtka Live Installer starting…
+
+  Once ready, open http://proksi.local:5000 on another device
+  on your network. The exact URL will appear below.
+

iso/overlay/airootfs/etc/systemd/system/furtka-issue.service

@@ -0,0 +1,12 @@
+[Unit]
+Description=Write Furtka /etc/issue with current IP for the console welcome
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=oneshot
+ExecStart=/usr/local/bin/furtka-update-issue
+RemainAfterExit=yes
+
+[Install]
+WantedBy=multi-user.target

iso/overlay/airootfs/etc/systemd/system/multi-user.target.wants/furtka-issue.service

@@ -0,0 +1 @@
+../furtka-issue.service

iso/overlay/airootfs/usr/local/bin/furtka-update-issue

@@ -0,0 +1,23 @@
+#!/bin/bash
+# Regenerates /etc/issue so the live-ISO console tells the user which URL
+# to open in their browser. Shows proksi.local (via avahi/mDNS) as the
+# preferred URL and the raw IP as a fallback for networks where mDNS
+# doesn't work. Reload at the end nudges agetty to redraw.
+set -e
+
+ip=$(ip -4 -o addr show scope global 2>/dev/null | awk '{print $4}' | cut -d/ -f1 | head -1)
+
+{
+    echo
+    echo "  Open Furtka in a browser on another device on your network:"
+    echo
+    echo "      http://proksi.local:5000   (easy — try this first)"
+    if [ -n "$ip" ]; then
+        echo "      http://${ip}:5000   (fallback if the first doesn't work)"
+    fi
+    echo
+    echo "  Then follow the wizard to install Furtka on this machine."
+    echo
+} > /etc/issue
+
+agetty --reload 2>/dev/null || true

webinstaller/app.py

@@ -5,7 +5,7 @@ import subprocess
 from pathlib import Path
 
 from drives import list_scored_devices
-from flask import Flask, redirect, render_template, request, url_for
+from flask import Flask, jsonify, redirect, render_template, request, url_for
 
 app = Flask(__name__)
 
@@ -269,5 +269,25 @@ def install_log_view():
     )
 
 
+@app.route("/install/log.json")
+def install_log_json():
+    log = INSTALL_LOG.read_text() if INSTALL_LOG.exists() else ""
+    return jsonify(log=log, progress=parse_install_progress(log))
+
+
+@app.route("/install/reboot", methods=["POST"])
+def install_reboot():
+    # Only allow rebooting once the install has actually finished — we don't
+    # want a panicked click during install to reboot mid-pacstrap.
+    log = INSTALL_LOG.read_text() if INSTALL_LOG.exists() else ""
+    if parse_install_progress(log)["status"] != "done":
+        return redirect(url_for("install_log_view"))
+    subprocess.Popen(
+        ["/usr/bin/systemctl", "reboot"],
+        start_new_session=True,
+    )
+    return render_template("install/rebooting.html")
+
+
 if __name__ == "__main__":
     app.run(debug=True, port=5000)

webinstaller/templates/install/log.html

@@ -2,29 +2,96 @@
 
 {% block title %}Installing… · Furtka Installer{% endblock %}
 {% block head_extra %}
+{# Fallback for users with JS disabled — otherwise the JS below takes over
+   and updates in-place so the log <details> doesn't re-collapse. #}
+<noscript>
 {% if progress.status == "running" %}<meta http-equiv="refresh" content="3">{% endif %}
+</noscript>
 {% endblock %}
 {% block step_indicator %}<span class="step-indicator">Installing</span>{% endblock %}
 
 {% block content %}
+<h1 id="install-heading">
+{% if progress.status == "done" %}Furtka is ready
+{% elif progress.status == "error" %}Installation hit a snag
+{% else %}Installing Furtka{% endif %}
+</h1>
+<p class="lede" id="install-lede">
+{% if progress.status == "done" %}Installation finished. <strong>Remove the installer USB / eject the ISO</strong>, then click Reboot.
+{% elif progress.status == "error" %}Something went wrong. Open the details below and share them so we can help.
+{% else %}This takes a few minutes. Don't close this page or power off the machine.{% endif %}
+</p>
+
 {% if progress.status == "done" %}
-<h1>Furtka is ready</h1>
-<p class="lede">Installation finished. Remove the USB / eject the installer image, then reboot.</p>
-{% elif progress.status == "error" %}
-<h1>Installation hit a snag</h1>
-<p class="lede">Something went wrong. Open the details below and share them so we can help.</p>
-{% else %}
-<h1>Installing Furtka</h1>
-<p class="lede">This takes a few minutes. Don't close this page or power off the machine.</p>
+<form method="post" action="{{ url_for('install_reboot') }}"
+      onsubmit="return confirm('Have you removed the installer USB / ejected the ISO? Click OK to reboot.');">
+    <div class="actions">
+        <button type="submit" class="btn btn-primary">Reboot now</button>
+    </div>
+</form>
 {% endif %}
 
 <div class="progress" role="progressbar" aria-valuemin="0" aria-valuemax="100" aria-valuenow="{{ progress.percent }}">
-    <div class="progress-bar{% if progress.status == 'error' %} progress-bar-error{% endif %}{% if progress.status == 'done' %} progress-bar-done{% endif %}" style="width: {{ progress.percent }}%;"></div>
+    <div id="progress-bar" class="progress-bar{% if progress.status == 'error' %} progress-bar-error{% endif %}{% if progress.status == 'done' %} progress-bar-done{% endif %}" style="width: {{ progress.percent }}%;"></div>
 </div>
-<p class="progress-phase">{{ progress.phase }} · {{ progress.percent }}%</p>
+<p class="progress-phase"><span id="progress-phase">{{ progress.phase }}</span> · <span id="progress-percent">{{ progress.percent }}</span>%</p>
 
 <details class="log-details">
     <summary>Show details</summary>
-    <pre class="log">{{ log or "(waiting for install to start)" }}</pre>
+    <pre id="install-log" class="log">{{ log or "(waiting for install to start)" }}</pre>
 </details>
+
+<script>
+(function () {
+    var initialStatus = {{ progress.status | tojson }};
+    if (initialStatus !== 'running') return;
+
+    var bar = document.getElementById('progress-bar');
+    var phaseEl = document.getElementById('progress-phase');
+    var percentEl = document.getElementById('progress-percent');
+    var logEl = document.getElementById('install-log');
+    var headingEl = document.getElementById('install-heading');
+    var ledeEl = document.getElementById('install-lede');
+
+    var HEADINGS = {
+        done: 'Furtka is ready',
+        error: 'Installation hit a snag',
+    };
+    var LEDES = {
+        done: 'Installation finished. Remove the USB / eject the installer image, then reboot.',
+        error: 'Something went wrong. Open the details below and share them so we can help.',
+    };
+
+    function tick() {
+        fetch('{{ url_for("install_log_json") }}', { cache: 'no-store' })
+            .then(function (r) { return r.json(); })
+            .then(function (data) {
+                var p = data.progress;
+                bar.style.width = p.percent + '%';
+                phaseEl.textContent = p.phase;
+                percentEl.textContent = p.percent;
+                if (logEl.textContent !== data.log) {
+                    var atBottom = logEl.scrollTop + logEl.clientHeight >= logEl.scrollHeight - 8;
+                    logEl.textContent = data.log || '(waiting for install to start)';
+                    if (atBottom) logEl.scrollTop = logEl.scrollHeight;
+                }
+                if (p.status === 'done') {
+                    // Reload so the server-rendered Done state (with the
+                    // Reboot button) replaces the running-state markup.
+                    window.location.reload();
+                    return;
+                }
+                if (p.status === 'error') {
+                    bar.classList.add('progress-bar-error');
+                    headingEl.textContent = HEADINGS.error;
+                    ledeEl.textContent = LEDES.error;
+                    return;
+                }
+                setTimeout(tick, 3000);
+            })
+            .catch(function () { setTimeout(tick, 3000); });
+    }
+    setTimeout(tick, 3000);
+})();
+</script>
 {% endblock %}

webinstaller/templates/install/rebooting.html

@@ -0,0 +1,10 @@
+{% extends "base.html" %}
+
+{% block title %}Rebooting · Furtka Installer{% endblock %}
+{% block step_indicator %}<span class="step-indicator">Done</span>{% endblock %}
+
+{% block content %}
+<h1>Rebooting…</h1>
+<p class="lede">The machine is restarting. This page will stop responding in a moment — that's expected.</p>
+<p>When the machine comes back up, log in with the username and password you set during the install.</p>
+{% endblock %}