release: v0.19.0

Release v0.19.0. See the `## [0.19.0] — 2026-09-29` section of
[CHANGELOG.md](https://github.com/ralksta/immich-folio/blob/dev/CHANGELOG.md)
for the full list.

Highlights: client proofing links (#683), custom content pages (#738),
asset picker search (#740), concurrent-edit detection (#742), env-locked
settings (#739), an accessibility baseline (#741), three security fixes
with advisories (#737, #755, #759), and a pre-release quality pass
(#780–#797).

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: ralksta <ralksta@users.noreply.github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
Co-authored-by: Ralf <rohlenbo79@gmail.com>
Co-authored-by: Paul Thies <110185070+ImScheinox@users.noreply.github.com>
Co-authored-by: lancetm714 <108419425+lancetm714@users.noreply.github.com>
Co-authored-by: Lance Martin <lancetaylor95@gmail.com>

app/admin/components/useVersionedSave.ts

@@ -0,0 +1,97 @@
+'use client';
+
+/**
+ * Saving a content file without clobbering a change made elsewhere (#601).
+ *
+ * Each editor keeps the `version` its GET returned in a ref and saves through
+ * this hook, which sends it as `If-Match`. When the server answers 409 with
+ * `conflict: true` — the file was saved from another tab or device, edited by
+ * hand, or restored from a backup since it was loaded — the operator picks:
+ *
+ * - Reload: throw away this editor's edits and load the file as it is now.
+ * - Overwrite anyway: save again against the new version, replacing that change.
+ * - Keep editing (cancel): nothing happens; the edits and their draft stay.
+ *
+ * Other 409s (a rename onto a taken slug) carry no `conflict` flag and are
+ * returned like any other failure.
+ */
+
+import { useCallback, type MutableRefObject } from 'react';
+import { useChoice } from './ConfirmDialog';
+
+/** The If-Match header for a version, or none before the first load. */
+export function ifMatch(version: string | null): Record<string, string> {
+  return version ? { 'If-Match': `"${version}"` } : {};
+}
+
+/** The body of any JSON answer; routes return objects. */
+export type SaveData = Record<string, unknown> & { error?: string };
+
+export type VersionedSaveResult =
+  | { kind: 'saved'; res: Response; data: SaveData }
+  | { kind: 'failed'; res: Response; data: SaveData | null }
+  | { kind: 'reload' }
+  | { kind: 'keep' };
+
+export function isEditConflict(res: Response, data: unknown): data is { version: string } {
+  return (
+    res.status === 409 &&
+    !!data &&
+    typeof data === 'object' &&
+    (data as { conflict?: unknown }).conflict === true &&
+    typeof (data as { version?: unknown }).version === 'string'
+  );
+}
+
+type ConflictChoice = 'overwrite' | 'reload';
+
+/**
+ * `what` names the file in the dialog ("The settings", "This entry").
+ * A network failure throws, as a plain fetch would.
+ */
+export function useVersionedSave() {
+  const choose = useChoice();
+
+  return useCallback(
+    async (
+      url: string,
+      body: unknown,
+      versionRef: MutableRefObject<string | null>,
+      what: string,
+    ): Promise<VersionedSaveResult> => {
+      let version = versionRef.current;
+      for (;;) {
+        const res = await fetch(url, {
+          method: 'PUT',
+          headers: { 'Content-Type': 'application/json', ...ifMatch(version) },
+          body: JSON.stringify(body),
+        });
+        const data = (await res.json().catch(() => null)) as SaveData | null;
+
+        if (isEditConflict(res, data)) {
+          const choice = await choose<ConflictChoice>({
+            title: 'Changed elsewhere',
+            message: `${what} was changed since you opened it — in another tab, on another device, by hand or by a backup restore. Saving now would replace that change.`,
+            actions: [
+              { id: 'overwrite', label: 'Overwrite anyway' },
+              { id: 'reload', label: 'Reload (discard mine)' },
+            ],
+            cancelLabel: 'Keep editing',
+          });
+          if (choice === 'overwrite') {
+            version = data.version;
+            continue;
+          }
+          return { kind: choice === 'reload' ? 'reload' : 'keep' };
+        }
+
+        if (res.ok && data) {
+          if (typeof data.version === 'string') versionRef.current = data.version;
+          return { kind: 'saved', res, data };
+        }
+        return { kind: 'failed', res, data };
+      }
+    },
+    [choose],
+  );
+}