Add reproducible build system, native Unraid plugin, and WebUI

- versions.env pins podman, conmon, crun, netavark, aardvark-dns, passt,
  and fuse-overlayfs to verified upstream source checksums; SlackBuild
  recipes, scripts/build-packages.sh, checksums.sh, release.sh, and
  update-versions.sh implement the reproducible pipeline; GitHub Actions
  workflows build in a Slackware container and publish releases without
  committing any binaries.

- plugin/podman.plg installs/updates/removes all eight packages (the
  seven components plus the plugin's own unraid-podman scaffolding
  package) via upgradepkg, using the official Unraid array-event hook
  mechanism (event/disks_mounted, event/stopping) instead of editing
  /boot/config/go. rc.podman and the sbin/ helper scripts implement
  storage creation, config seeding/sync, preflight checks, autostart
  with per-container Safe-Mode, and package verify/update/rollback.

- webui/plugins/podman implements the Dashboard, Containers, Pods,
  Images, Volumes, Networks, Logs, Terminal, Compose, and Settings
  panels against the approved mockup (webui/mockups/prototype.html),
  talking to podman system service exclusively via PodmanClient.php
  (libpod REST API over the Unix socket), with two documented
  exceptions: Terminal's one-shot exec model and Compose's use of the
  podman compose CLI, since libpod has no REST equivalent for either.

- docs/ARCHITECTURE.md and docs/ROADMAP.md record the design decisions
  and honest current status (syntax-checked, unit- and
  integration-tested against fake sockets/servers; not yet run against
  a real Unraid/Podman/Slackware system).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

webui/plugins/podman/javascript/app.js

@@ -0,0 +1,186 @@
+/**
+ * javascript/app.js
+ *
+ * Shared runtime for the Podman plugin page: the AJAX helper every panel
+ * module uses to talk to webui/plugins/podman/ajax/*.php, small DOM
+ * utilities to avoid repeating the same escaping/formatting logic in ten
+ * places, and the sub-tab router that shows/hides panels and lazily
+ * initializes each one's module the first time it's opened.
+ *
+ * Loaded first (before any panel module) — see Podman.page.
+ */
+window.Podman = (function () {
+  'use strict';
+
+  const BASE = '/plugins/podman/ajax/';
+
+  /**
+   * Calls one ajax/<file>.php?action=<action> endpoint and resolves with
+   * response.data, or rejects with an Error carrying the server's message
+   * — every ajax/*.php endpoint replies with the same {ok, data|error}
+   * envelope (see include/helpers.php's podman_json_response/_error), so
+   * this one function is the only place that envelope shape is known.
+   *
+   * @param {string} file      e.g. "containers"
+   * @param {string} action    e.g. "list"
+   * @param {('GET'|'POST')} method
+   * @param {object|null} body sent as JSON for POST
+   * @param {object} query     extra query-string params (e.g. {id: "..."})
+   */
+  function call(file, action, method, body, query) {
+    const params = new URLSearchParams(Object.assign({ action: action }, query || {}));
+    const url = BASE + file + '.php?' + params.toString();
+
+    const opts = { method: method, headers: {} };
+    if (body !== undefined && body !== null) {
+      opts.headers['Content-Type'] = 'application/json';
+      opts.body = JSON.stringify(body);
+    }
+
+    return fetch(url, opts)
+      .then(function (res) {
+        return res.json().then(function (envelope) {
+          if (!envelope.ok) {
+            throw new Error(envelope.error || ('Request failed (' + res.status + ')'));
+          }
+          return envelope.data;
+        });
+      });
+  }
+
+  function get(file, action, query) {
+    return call(file, action, 'GET', null, query);
+  }
+
+  function post(file, action, body) {
+    return call(file, action, 'POST', body || {}, {});
+  }
+
+  // --- DOM helpers ---------------------------------------------------------
+
+  function escapeHtml(value) {
+    return String(value == null ? '' : value).replace(/[&<>"']/g, function (c) {
+      return { '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;' }[c];
+    });
+  }
+
+  function el(id) {
+    return document.getElementById(id);
+  }
+
+  function formatBytes(bytes) {
+    if (!bytes || bytes <= 0) return '0 B';
+    const units = ['B', 'KB', 'MB', 'GB', 'TB'];
+    const i = Math.min(Math.floor(Math.log(bytes) / Math.log(1024)), units.length - 1);
+    const value = bytes / Math.pow(1024, i);
+    return (value >= 100 || i === 0 ? value.toFixed(0) : value.toFixed(1)) + ' ' + units[i];
+  }
+
+  function formatDuration(seconds) {
+    if (seconds == null) return '—';
+    if (seconds < 60) return seconds + 's';
+    const days = Math.floor(seconds / 86400);
+    const hours = Math.floor((seconds % 86400) / 3600);
+    const minutes = Math.floor((seconds % 3600) / 60);
+    if (days > 0) return days + 'd ' + hours + 'h';
+    if (hours > 0) return hours + 'h ' + minutes + 'm';
+    return minutes + 'm';
+  }
+
+  function formatRelativeTime(unixSeconds) {
+    if (!unixSeconds) return '—';
+    const diff = Math.max(0, Math.floor(Date.now() / 1000) - unixSeconds);
+    if (diff < 60) return 'just now';
+    if (diff < 3600) return Math.floor(diff / 60) + 'm ago';
+    if (diff < 86400) return Math.floor(diff / 3600) + 'h ago';
+    return Math.floor(diff / 86400) + 'd ago';
+  }
+
+  /** Status string (from libpod's container "State") -> chip color class. */
+  function stateChipClass(state) {
+    switch (state) {
+      case 'running': return 'podman-chip-good';
+      case 'paused': return 'podman-chip-warn';
+      case 'exited':
+      case 'created': return 'podman-chip-neutral';
+      default: return 'podman-chip-bad';
+    }
+  }
+
+  function loadingRow(colspan, label) {
+    return '<tr><td colspan="' + colspan + '" class="podman-loading">' + escapeHtml(label || 'Loading…') + '</td></tr>';
+  }
+
+  function errorRow(colspan, message) {
+    return '<tr><td colspan="' + colspan + '" class="podman-error">' + escapeHtml(message) + '</td></tr>';
+  }
+
+  // --- Panel router ----------------------------------------------------------
+
+  const panelModules = {};
+  const initialized = {};
+
+  /** Called by each panel's own JS file (e.g. containers.js) to register itself. */
+  function registerPanel(name, module) {
+    panelModules[name] = module;
+  }
+
+  function activatePanel(name) {
+    document.querySelectorAll('.podman-subnav button').forEach(function (btn) {
+      btn.classList.toggle('active', btn.dataset.panel === name);
+    });
+    document.querySelectorAll('.podman-panel').forEach(function (panel) {
+      panel.classList.toggle('active', panel.id === 'podman-panel-' + name);
+    });
+
+    const module = panelModules[name];
+    if (!module) return;
+
+    if (!initialized[name]) {
+      initialized[name] = true;
+      if (typeof module.init === 'function') module.init();
+    } else if (typeof module.refresh === 'function') {
+      module.refresh();
+    }
+  }
+
+  function boot() {
+    const subnav = document.querySelector('.podman-subnav');
+    if (!subnav) return;
+
+    subnav.addEventListener('click', function (e) {
+      const btn = e.target.closest('button[data-panel]');
+      if (btn) activatePanel(btn.dataset.panel);
+    });
+
+    const refreshBtn = el('podman-refresh-all');
+    if (refreshBtn) {
+      refreshBtn.addEventListener('click', function () {
+        const active = document.querySelector('.podman-subnav button.active');
+        if (active) activatePanel(active.dataset.panel);
+      });
+    }
+
+    // Activate whichever panel is marked active in the initial HTML
+    // (Dashboard, by default — see Podman.page).
+    const initial = document.querySelector('.podman-subnav button.active');
+    activatePanel(initial ? initial.dataset.panel : 'dashboard');
+  }
+
+  document.addEventListener('DOMContentLoaded', boot);
+
+  return {
+    get: get,
+    post: post,
+    escapeHtml: escapeHtml,
+    el: el,
+    formatBytes: formatBytes,
+    formatDuration: formatDuration,
+    formatRelativeTime: formatRelativeTime,
+    stateChipClass: stateChipClass,
+    loadingRow: loadingRow,
+    errorRow: errorRow,
+    registerPanel: registerPanel,
+    activatePanel: activatePanel,
+  };
+})();