web(review): scope date suggestion to EXIF Stripped tab + 'a' shortcut

- Gate the sidebar's "Suggested from path" row on /review?tab=stripped_exif
  instead of a per-photo TakenSrc heuristic — PhotoPrism stores a guessed
  TakenAt for stripped-EXIF photos too, so the heuristic was hiding the
  row even when a path-derived date was available.
- Same gate on the BulkActionBar's "Accept date & Keep" button.
- Extract acceptDateAndKeep() + cachedPhoto() into photoActions so the
  bar button and a new bare-'a' shortcut in gridKeyNav share one path.
- Show an 'A' kbd hint on the bar button.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

web/src/lib/components/sidebar/RightSidebar.svelte

@@ -6,6 +6,7 @@
 	PUT (Details fields need the full body).
 -->
 <script lang="ts">
+	import { page } from '$app/state';
 	import { createMutation, createQuery, useQueryClient } from '@tanstack/svelte-query';
 	import { toast } from 'svelte-sonner';
 	import {
@@ -128,19 +129,21 @@
 		commit({ Caption: caption, CaptionSrc: 'manual' });
 	}
 	const takenAtValid = $derived(takenAt === '' || isValidISODate(takenAt));
-	// Path-based date guess. Surfaced only when the photo's stored date is
-	// missing or untrusted — same heuristic the review adapter uses to
-	// bucket photos into `stripped_exif`. Tying it to the heuristic rather
-	// than a specific tab means the suggestion shows up wherever the user
-	// lands on a date-less photo (timeline drill-in, archive, etc.).
-	const needsDate = $derived(
-		!photo.TakenSrc || photo.TakenSrc === 'name' || !photo.TakenAt
+	// Path-based date guess. Scoped to the EXIF Stripped review tab: those
+	// are the photos with definitionally-untrusted dates, and showing the
+	// row anywhere else would compete with the existing TakenAt.
+	// PhotoPrism stores a TakenAt for stripped-EXIF photos too (filename
+	// guess or file mtime), so a per-photo "needs date" heuristic would
+	// silently hide the suggestion — the tab is the more reliable signal.
+	const onExifStrippedTab = $derived(
+		page.url.pathname === '/review' &&
+			page.url.searchParams.get('tab') === 'stripped_exif'
 	);
 	const dateSuggestion = $derived(
 		suggestDateFromPath({ fileName: photo.FileName, path: photo.Path })
 	);
 	const showDateSuggestion = $derived(
-		needsDate && !!dateSuggestion && dateSuggestion !== takenAt
+		onExifStrippedTab && !!dateSuggestion && dateSuggestion !== takenAt
 	);
 	function applyDateSuggestion() {
 		if (!dateSuggestion) return;