Show split branch option only when branch not conflicted

Enhance the split branches experience:
- Only show the option to split the branch if the branch is not conflicted, by evaluating the isBranchConflicted status with ReduxResult.
- Add isBranchConflicted method to stackService to query branch conflict state easily from context menu components.

This makes the split branch menu option conditional on the branch's conflict status, improving clarity and preventing unsupported actions.

Author: estib-vega

apps/desktop/src/components/v3/FileContextMenu.svelte

@@ -1,5 +1,6 @@
 <!-- This is a V3 replacement for `FileContextMenu.svelte` -->
 <script lang="ts">
+	import ReduxResult from '$components/ReduxResult.svelte';
 	import { ActionService } from '$lib/actions/actionService.svelte';
 	import { AIService } from '$lib/ai/service';
 	import { writeClipboard } from '$lib/backend/clipboard';
@@ -75,6 +76,10 @@
 	const userSettings = getContextStoreBySymbol<Settings, Writable<Settings>>(SETTINGS);
 	const isUncommitted = $derived(selectionId.type === 'worktree');
 	const isBranchFiles = $derived(selectionId.type === 'branch');
+	const selectionBranchName = $derived(
+		selectionId.type === 'branch' ? selectionId.branchName : undefined
+	);
+
 	const user = getContextStore(User);
 	const isAdmin = $derived($user.role === 'admin');
 
@@ -380,21 +385,33 @@
 							}
 						}}
 					/>
-					{#if isBranchFiles && isAdmin}
-						<ContextMenuItem
-							label="Split off changes"
-							onclick={() => {
-								split(changes);
-								contextMenu.close();
-							}}
-						/>
-						<ContextMenuItem
-							label="Split into dependent branch"
-							onclick={() => {
-								splitIntoDependentBranch(changes);
-								contextMenu.close();
-							}}
-						/>
+
+					{#if isBranchFiles && stackId && selectionBranchName && isAdmin}
+						{@const branchIsConflicted = stackService.isBranchConflicted(
+							projectId,
+							stackId,
+							selectionBranchName
+						)}
+						<ReduxResult {projectId} result={branchIsConflicted?.current}>
+							{#snippet children(isConflicted)}
+								{#if isConflicted === false}
+									<ContextMenuItem
+										label="Split off changes"
+										onclick={() => {
+											split(changes);
+											contextMenu.close();
+										}}
+									/>
+									<ContextMenuItem
+										label="Split into dependent branch"
+										onclick={() => {
+											splitIntoDependentBranch(changes);
+											contextMenu.close();
+										}}
+									/>
+								{/if}
+							{/snippet}
+						</ReduxResult>
 					{/if}
 				{/if}
 			</ContextMenuSection>

apps/desktop/src/lib/stacks/stackService.svelte.ts

@@ -747,6 +747,18 @@ export class StackService {
 		return await this.api.endpoints.newBranchName.fetch({ projectId }, { forceRefetch: true });
 	}
 
+	isBranchConflicted(projectId: string, stackId: string, branchName: string) {
+		return this.api.endpoints.stackDetails.useQuery(
+			{ projectId, stackId },
+			{
+				transform: ({ branchDetails }) => {
+					const branch = branchDetailsSelectors.selectById(branchDetails, branchName);
+					return branch?.isConflicted ?? false;
+				}
+			}
+		);
+	}
+
 	async normalizeBranchName(name: string) {
 		return await this.api.endpoints.normalizeBranchName.fetch({ name }, { forceRefetch: true });
 	}