Line numbers are places in import and export; fix stale scripts

Import: each row's place is its line number, so blank lines leave a
place empty; a fully numbered text file ("38. Title") or a Rank column
gives places directly, and repeated numbers take the next free place.
Entries are added at those places (existing ones there move down), the
review shows each row's #, and the room check covers the highest place.

Export writes a blank line for every empty place, so line N is #N and a
file round-trips.

Static files now carry an ETag and unversioned ones are revalidated on
every load. Scripts import each other without a ?v= tag, so browsers kept
an hour-old import.js (with the "null" bug) after an update.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/static/js/import.js

@@ -32,7 +32,7 @@ export function openImport({ list, cat, onListChange, onDone }) {
     dialogHead("Import a list", () => dlg),
     h("div", { class: "dialog-body stack" },
       h("p", { class: "muted" },
-        `Entries are added after your last one, in the file's order. Use one title per line, or a CSV with columns like Title, Year, ${artistWord(cat)} and Note. `,
+        `Line 1 becomes #1, line 38 becomes #38, and a blank line leaves its place empty${list.itemCount ? " (entries already at those places move down to make room)" : ""}. Use one title per line, or a CSV with columns like Title, Year, ${artistWord(cat)} and Note. `,
         "Each one is looked up and matched for you; anything Canon isn't sure about is left for you to check."),
       drop,
       text,
@@ -117,14 +117,18 @@ export function openImport({ list, cat, onListChange, onDone }) {
         ].filter(Boolean);
       summary.textContent = parts.join(" · ");
 
-      const n = chosen().length;
-      const free = list.maxItems - list.itemCount;
-      go.disabled = matching || n === 0 || n > free;
+      const picked = chosen();
+      const n = picked.length;
+      const lastPlace = Math.max(0, ...picked.map((e) => e.row.place));
+      const fits = list.itemCount + n <= list.maxItems && lastPlace <= list.maxItems;
+      go.disabled = matching || n === 0 || !fits;
       go.textContent = matching ? "Matching…" : `Import ${fmt.format(n)} ${n === 1 ? "entry" : "entries"}`;
-      room.hidden = matching || n <= free;
+      room.hidden = matching || n === 0 || fits;
       if (!room.hidden) {
-        const want = Math.min(list.itemCount + n, 65535);
-        room.replaceChildren(icon("info"), `This list has room for ${fmt.format(free)} more. `,
+        const want = Math.min(Math.max(list.itemCount + n, lastPlace), 65535);
+        room.replaceChildren(icon("info"), lastPlace > list.maxItems
+          ? `The file goes up to #${fmt.format(lastPlace)}, but this list ends at #${fmt.format(list.maxItems)}. `
+          : `This list has room for ${fmt.format(list.maxItems - list.itemCount)} more. `,
           h("button", {
             type: "button", class: "btn btn--sm", onclick: async (e) => {
               busy(e.currentTarget, true);
@@ -163,7 +167,7 @@ export function openImport({ list, cat, onListChange, onDone }) {
 
       const li = h("li", { class: `import-row is-${e.state}`, "data-i": e.i },
         h("div", { class: "import-row-head" },
-          h("span", { class: "import-num" }, `${e.i + 1}.`),
+          h("span", { class: "import-num" }, `#${row.place}`),
           h("div", { class: "import-src" }, h("b", {}, row.title), asWritten && h("span", { class: "muted small" }, ` ${asWritten}`)),
           badge),
       );
@@ -299,9 +303,9 @@ export function openImport({ list, cat, onListChange, onDone }) {
         ? {
           title: r.title, subtitle: r.subtitle, year: r.year, externalUrl: r.externalUrl, imageUrl: r.imageUrl,
           provider: r.provider, providerId: r.providerId, extra: { ...(r.extra || {}) }, description: r.overview || "",
-          details: true, note: e.row.note || "",
+          details: true, note: e.row.note || "", rank: e.row.place,
         }
-        : { title: e.row.title, subtitle: e.row.subtitle || "", year: e.row.year || "", note: e.row.note || "", extra: {} };
+        : { title: e.row.title, subtitle: e.row.subtitle || "", year: e.row.year || "", note: e.row.note || "", extra: {}, rank: e.row.place };
       try {
         const res = await api("POST", `/api/lists/${list.id}/items`, payload);
         added++;