hooks are the highest precedence in context merging followed by invocation.

Fixes #43

Author: justinabrahms

src/main/java/dev/openfeature/javasdk/OpenFeatureClient.java

@@ -64,7 +64,7 @@ private <T> FlagEvaluationDetails<T> evaluateFlag(FlagValueType type, String key
         try {
             EvaluationContext ctxFromHook = hookSupport.beforeHooks(type, hookCtx, mergedHooks, hints);
 
-            EvaluationContext invocationCtx = EvaluationContext.merge(ctxFromHook, ctx);
+            EvaluationContext invocationCtx = EvaluationContext.merge(ctx, ctxFromHook);
 
             // merge of: API.context, client.context, invocation.context
             EvaluationContext mergedCtx = EvaluationContext.merge(

src/test/java/dev/openfeature/javasdk/HookSpecTest.java

@@ -455,14 +455,15 @@ public void finallyAfter(HookContext<Boolean> ctx, Map<String, Object> hints) {
 
     }
 
-    @Specification(number="4.3.4", text="When before hooks have finished executing, any resulting evaluation context MUST be merged with the invocation evaluation context with the invocation evaluation context taking precedence in the case of any conflicts.")
+    @Specification(number="4.3.4", text="When before hooks have finished executing, any resulting evaluation context MUST be merged with the existing evaluation context in the following order: before-hook (highest precedence), invocation, client, api (lowest precedence).")
     @Test void mergeHappensCorrectly() {
         EvaluationContext hookCtx = new EvaluationContext();
-        hookCtx.addStringAttribute("test", "broken");
+        hookCtx.addStringAttribute("test", "works");
         hookCtx.addStringAttribute("another", "exists");
 
         EvaluationContext invocationCtx = new EvaluationContext();
-        invocationCtx.addStringAttribute("test", "works");
+        invocationCtx.addStringAttribute("something", "here");
+        invocationCtx.addStringAttribute("test", "broken");
 
         Hook<Boolean> hook = mockBooleanHook();
         when(hook.before(any(), any())).thenReturn(Optional.of(hookCtx));
@@ -485,6 +486,7 @@ public void finallyAfter(HookContext<Boolean> ctx, Map<String, Object> hints) {
         EvaluationContext ec = captor.getValue();
         assertEquals("works", ec.getStringAttribute("test"));
         assertEquals("exists", ec.getStringAttribute("another"));
+        assertEquals("here", ec.getStringAttribute("something"));
     }
 
     @Specification(number="4.4.3", text="If a finally hook abnormally terminates, evaluation MUST proceed, including the execution of any remaining finally hooks.")