Add all eligible files to beta setup

src/routes/betas/new/+page.svelte

@@ -84,6 +84,7 @@
         allowLeave = false;
     let hasLinkedSetup = $state(false);
     let loadingVersions = $state<Set<number>>(new Set());
+    let addingAllFiles = $state(false);
     const rowRequests = new Map<number, number>();
     let versionRequest = 0;
     let betaLabel = $state('');
@@ -103,6 +104,9 @@
                     picks.some((pick) => pick.scriptId === file.id && versionsFor(pick).length > 0))
         )
     );
+    const remainingFiles = $derived(
+        eligibleFiles.filter((file) => !picks.some((pick) => pick.scriptId === file.id))
+    );
     const filesReady = $derived(
         picks.length > 0 &&
             picks.every(
@@ -526,6 +530,22 @@
                 loadingVersions = new Set([...loadingVersions].filter((key) => key !== pick.key));
         }
     }
+    async function addAllFiles() {
+        if (addingAllFiles || loadingVersions.size || !remainingFiles.length) return;
+        const selected = picks.filter((pick) => pick.scriptId !== null);
+        const additions = remainingFiles.map((file) => ({
+            key: nextKey++,
+            scriptId: file.id,
+            versionId: null
+        }));
+        picks = [...selected, ...additions];
+        addingAllFiles = true;
+        try {
+            await Promise.all(additions.map((_, index) => onPickFile(selected.length + index)));
+        } finally {
+            addingAllFiles = false;
+        }
+    }
     function toggleServer(name: string) {
         const next = new Set(pickedServers);
         if (next.has(name)) next.delete(name);
@@ -749,11 +769,21 @@
                                     </p>{/if}{/if}
                         </section>{/each}
                 </div>
-                <Button
-                    onclick={() =>
-                        (picks = [...picks, { key: nextKey++, scriptId: null, versionId: null }])}
-                    disabled={picks.length >= eligibleFiles.length}>Add file</Button
-                >
+                <div class="actions">
+                    <Button
+                        onclick={() =>
+                            (picks = [
+                                ...picks,
+                                { key: nextKey++, scriptId: null, versionId: null }
+                            ])}
+                        disabled={picks.length >= eligibleFiles.length}>Add file</Button
+                    >
+                    <Button
+                        onclick={addAllFiles}
+                        disabled={!remainingFiles.length || loadingVersions.size > 0}
+                        loading={addingAllFiles}>Add all eligible files</Button
+                    >
+                </div>
                 <p class="muted">
                     Combine files for different games in one beta. Each file installs only on
                     servers matching its scope, and every file needs at least one test participant.