Add Docker deployment and per-player secret-link viewers.

Each player gets an isolated SQLite viewer via a unique URL without login, with landing page warnings to save the link and compose-based hosting for sharing with others.

Co-authored-by: Cursor <cursoragent@cursor.com>

static/landing.js

@@ -0,0 +1,42 @@
+document.addEventListener("DOMContentLoaded", async () => {
+  await I18n.init();
+  applyStaticI18n();
+  setupLanguage();
+  setupCreate();
+});
+
+function applyStaticI18n() {
+  document.querySelectorAll("[data-i18n]").forEach((el) => {
+    el.textContent = t(el.dataset.i18n);
+  });
+}
+
+function setupLanguage() {
+  const sel = document.getElementById("locale-select");
+  sel.value = I18n.getPreference();
+  sel.addEventListener("change", async (e) => {
+    await I18n.setPreference(e.target.value);
+    applyStaticI18n();
+  });
+}
+
+function setupCreate() {
+  const btn = document.getElementById("create-viewer");
+  const status = document.getElementById("create-status");
+  btn.addEventListener("click", async () => {
+    btn.disabled = true;
+    status.hidden = false;
+    status.textContent = t("viewer.creating");
+    status.className = "landing-hint";
+    try {
+      const res = await fetch("/api/viewers", { method: "POST" });
+      const data = await res.json();
+      if (!res.ok) throw new Error(data.error || t("viewer.createFailed"));
+      window.location.href = data.url;
+    } catch (err) {
+      status.textContent = err.message;
+      status.className = "landing-hint landing-hint-error";
+      btn.disabled = false;
+    }
+  });
+}