fix: disable engine analysis during drill play via enabled flag

The analysis controller's useEngineAnalysis hook has its own internal
tree controller that navigates the drill's game tree. Even though we
stopped syncing currentNode, the internal controller still tracked
tree changes and fired stockfish.streamEvaluations() — which calls
stopEvaluation() and kills the background analysis's in-progress
evaluation (explaining depth 8 instead of 18).

Added an 'enabled' parameter to useEngineAnalysis and
useAnalysisController. During drill play (analysisEnabled=false,
continueAnalyzingMode=false), both Maia and Stockfish effects in
useEngineAnalysis are completely skipped.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: ashtonanderson

src/hooks/useAnalysisController/useAnalysisController.ts

@@ -26,6 +26,7 @@ export const useAnalysisController = (
   game: AnalyzedGame,
   initialOrientation?: 'white' | 'black',
   enableAutoSave = true,
+  enableEngineAnalysis = true,
 ) => {
   const defaultOrientation = initialOrientation
     ? initialOrientation
@@ -86,6 +87,7 @@ export const useAnalysisController = (
     deepAnalysisController.progress.isAnalyzing
       ? deepAnalysisController.config.targetDepth
       : 18,
+    enableEngineAnalysis,
   )
 
   const availableMoves = useMemo(() => {

src/hooks/useAnalysisController/useEngineAnalysis.ts

@@ -15,6 +15,7 @@ export const useEngineAnalysis = (
   currentMaiaModel: string,
   setAnalysisState: React.Dispatch<React.SetStateAction<number>>,
   targetDepth = 18,
+  enabled = true,
 ) => {
   const maia = useContext(MaiaEngineContext)
   const stockfish = useContext(StockfishEngineContext)
@@ -78,7 +79,7 @@ export const useEngineAnalysis = (
   }
 
   useEffect(() => {
-    if (!currentNode) return
+    if (!currentNode || !enabled) return
 
     const board = new Chess(currentNode.fen)
     const nodeFen = currentNode.fen
@@ -163,10 +164,11 @@ export const useEngineAnalysis = (
     inProgressAnalyses,
     maia,
     setAnalysisState,
+    enabled,
   ])
 
   useEffect(() => {
-    if (!currentNode) return
+    if (!currentNode || !enabled) return
 
     const shouldForceStockfishRerun =
       stockfishDebugRerunToken > lastConsumedStockfishRerunTokenRef.current
@@ -281,5 +283,6 @@ export const useEngineAnalysis = (
     stockfishDebugRerunToken,
     currentNode?.analysis.maia?.[currentMaiaModel]?.policy,
     currentNode?.mainChild?.move,
+    enabled,
   ])
 }

src/pages/openings/index.tsx

@@ -180,6 +180,7 @@ const OpeningsPage: NextPage = () => {
     },
     controller.currentDrill?.playerColor || 'white',
     false, // Disable auto-saving on openings page
+    controller.analysisEnabled || controller.continueAnalyzingMode, // Disable engine analysis during drill play
   )
 
   // Sync analysis controller with current node — only when analysis is active