test(terminal): add integration tests for panel close confirmation

Tests cover: single idle terminal closes without dialog, multiple
terminals show close-all dialog, active process shows close-terminal
dialog, stop-processes dialog variant, cancel preserves state, confirm
disposes all terminals, and programmatic hide() keeps terminals alive.
Also adds _writeToActiveTerminal test helper to terminal extension.

Author: abose

src/extensionsIntegrated/Terminal/main.js

@@ -673,4 +673,19 @@ define(function (require, exports, module) {
     // Export for testing
     exports.CMD_VIEW_TERMINAL = CMD_VIEW_TERMINAL;
     exports.CMD_NEW_TERMINAL = CMD_NEW_TERMINAL;
+
+    /**
+     * Write data to the active terminal's PTY. Test-only helper.
+     * @param {string} data The text to send to the terminal.
+     * @return {Promise}
+     */
+    exports._writeToActiveTerminal = function (data) {
+        const active = _getActiveTerminal();
+        if (!active || !active.isAlive) {
+            return Promise.reject(new Error("No active terminal"));
+        }
+        return nodeConnector.execPeer("writeTerminal", {
+            id: active.id, data
+        });
+    };
 });

test/UnitTestSuite.js

@@ -140,6 +140,7 @@ define(function (require, exports, module) {
     require("spec/Extn-HTMLCodeHints-Lint-integ-test");
     require("spec/Extn-HtmlTagSyncEdit-integ-test");
     require("spec/Extn-Git-integ-test");
+    require("spec/Terminal-integ-test");
     // Node Tests
     require("spec/NodeConnection-test");
     // pro test suite optional components