fix: de-duplicate involved-scope results across pages in single-instance overviews (#70)

**Why.** The Issues and Pull Requests overviews fire one search request per involvement flag (created/assigned/mentioned/review-requested) and merge the results, so the same issue can resurface on a later page — created on page 1, assigned on page 2. The merged multi-instance overview already de-duplicates across pages with a pagination dedupe key, but the single-instance overview never set one, so loading more appended duplicate rows with duplicate Identifiable ids.

**What changed.** `SearchableOverviewView.init` sets the same `dedupeKey` the merged overview sets (`MergedSearchableOverviewView` line 71), routing pages through `PaginationState`'s existing cross-page dedupe. The `dedupeKey` doc comment is updated to match. `hasMore` switches to the contributed-new-items heuristic, which fits combined per-flag sources whose merged page size never matches the request limit.

**Verification.** New `PaginationStateDedupeTests` pin the keyed path: a key repeated across pages is filtered out on the later page, `hasMore` follows `!newItems.isEmpty` when `dedupeKey` is set (including a full page of already-seen keys ending pagination), and a reload resets the seen keys. Full `ForjiTests` suite passes (0 failed, iPhone 17 Pro, iOS 26.5). SwiftLint clean with the repo config.

I grant Stefan Hausotte an irrevocable, worldwide, royalty-free license to use, sublicense, and distribute my contribution, including through Apple's App Store under the project's App Store exception.

Reviewed-on: https://codeberg.org/secana/Forji/pulls/70

Forji/Forji/Helpers/PaginationState.swift

@@ -16,10 +16,10 @@ final class PaginationState<Item> {
     let pageSize: Int
     var cacheName: String?
 
-    /// Optional key extractor enabling cross-page de-duplication. Merged views set
-    /// this because they combine paginated results from several instances, where
-    /// the same item can resurface on a later page (overlapping involvement
-    /// queries) and the merged page size no longer matches `pageSize`.
+    /// Optional key extractor enabling cross-page de-duplication. Views that
+    /// combine several paginated sources set this (merged multi-instance lists,
+    /// or the per-flag involvement queries), because the same item can resurface
+    /// on a later page and the combined page size no longer matches `pageSize`.
     @ObservationIgnored var dedupeKey: ((Item) -> AnyHashable)?
     @ObservationIgnored private var seenKeys = Set<AnyHashable>()
 

Forji/Forji/Views/SearchableOverviewView.swift

@@ -59,6 +59,7 @@ struct SearchableOverviewView<Row: View, Detail: View, CreateView: View>: View {
 
         let state = PaginationState<Issue>()
         state.cacheName = issueType
+        state.dedupeKey = { $0.id }
         state.loadFromCache()
         _pagination = State(initialValue: state)
     }

Forji/ForjiTests/PaginationStateTests.swift

@@ -475,3 +475,50 @@ struct PaginationStateLoadMoreTests {
         #expect(!pagination.isLoading)
     }
 }
+
+// MARK: - Keyed de-duplication
+
+struct PaginationStateDedupeTests {
+
+    @Test @MainActor func loadMoreFiltersKeysSeenOnEarlierPages() async {
+        let pagination = PaginationState<String>(pageSize: 2)
+        pagination.dedupeKey = { $0 }
+        await pagination.reload { _, _ in ["a", "b"] }.value
+
+        // "b" resurfaces on page 2 — only "c" is new
+        await pagination.loadMore { _, _ in ["b", "c"] }
+        #expect(pagination.items == ["a", "b", "c"])
+        #expect(pagination.hasMore) // the page contributed a new item
+    }
+
+    @Test @MainActor func hasMoreFollowsNewItemsNotPageSize() async {
+        let pagination = PaginationState<String>(pageSize: 5)
+        pagination.dedupeKey = { $0 }
+        await pagination.reload { _, _ in ["a", "b"] }.value
+        #expect(pagination.hasMore) // 2 < pageSize 5, but the page contributed new items
+    }
+
+    @Test @MainActor func hasMoreFalseWhenFullPageIsAllDuplicates() async {
+        let pagination = PaginationState<String>(pageSize: 2)
+        pagination.dedupeKey = { $0 }
+        await pagination.reload { _, _ in ["a", "b"] }.value
+        #expect(pagination.hasMore)
+
+        // 2 >= pageSize 2, but every key was already seen -> pagination ends
+        await pagination.loadMore { _, _ in ["a", "b"] }
+        #expect(pagination.items == ["a", "b"])
+        #expect(!pagination.hasMore)
+    }
+
+    @Test @MainActor func reloadResetsSeenKeys() async {
+        let pagination = PaginationState<String>(pageSize: 2)
+        pagination.dedupeKey = { $0 }
+        await pagination.reload { _, _ in ["a", "b"] }.value
+        await pagination.loadMore { _, _ in ["b", "c"] }
+        #expect(pagination.items == ["a", "b", "c"])
+
+        // A fresh reload must accept keys seen in the previous cycle
+        await pagination.reload { _, _ in ["a", "b"] }.value
+        #expect(pagination.items == ["a", "b"])
+    }
+}