Remove eval history tracking and fix error semantics tests

- Remove unused eval history tracking from eval/core.clj
- Update eval tool tests to expect error? true for error cases

Author: Bruce Hauman

src/clojure_mcp/tools/eval/core.clj

@@ -72,10 +72,6 @@
         session-type (or session-type :default)
         conn (nrepl/open-connection nrepl-client)]
 
-    ;; Push to eval history if available
-    (when-let [state (::nrepl/state nrepl-client)]
-      (swap! state update :clojure-mcp.repl-tools/eval-history conj form-str))
-
     (try
       (let [session-id (nrepl/ensure-session nrepl-client conn session-type)
             eval-id (nrepl/new-eval-id)

test/clojure_mcp/tools/eval/tool_test.clj

@@ -101,7 +101,7 @@
 
   (testing "Evaluation with error"
     (let [result (test-tool-execution "(throw (Exception. \"test error\"))")]
-      (is (false? (:error? result)))
+      (is (true? (:error? result)))
       (is (= 1 (count (:result result))))
       (is (str/includes? (first (:result result)) "test error"))
       (is (str/includes? (first (:result result)) "Execution error"))))
@@ -123,7 +123,7 @@
   (testing "Evaluation with runtime error (no pre-evaluation linting)"
     ;; With delimiter-only checking, syntax errors are caught at runtime
     (let [result (test-tool-execution "(def ^:dynamic 1)")]
-      (is (false? (:error? result)))
+      (is (true? (:error? result)))
       (is (= 1 (count (:result result))))
       ;; Should have error from evaluation, not from linting
       (is (str/includes? (first (:result result)) "Syntax error")))))