AI Coding: Fix/improve instructions for cloud agents

Specifically:
* Fix the E2E test name
* Use the concise `crystal --version` as a smoke test rather than
  the verbose `crystal --help`

Author: davidfstr

.github/copilot-instructions.md

@@ -85,7 +85,7 @@ Error Handling:
 * Run `crystal --version` and ensure you see a result like `Crystal 2.0.2`.
     * If you see `crystal: command not found` then you probably need to activate a Python virtual environment first or use Poetry to run commands. Try `source venv3.14/bin/activate && crystal --version` first. If there is no `venv3.14` directory then try `poetry run crystal --version`.
 * Ensure you can run a unit test. Try `pytest tests/test_version.py` or `poetry run pytest ...`.
-* Ensure you can run an end-to-end test. Try `xvfb-run crystal test crystal.tests.test_main_window` or `poetry run xvfb-run crystal test ...`.
+* Ensure you can run an end-to-end test. Try `xvfb-run crystal test test_main_window` or `poetry run xvfb-run crystal test ...`.
     * If you see `xvfb-run: command not found` then remove `xvfb-run` from the command and try again.
     * If you see `Unable to access the X Display, is $DISPLAY set properly?` then you probably forgot to use `xvfb-run`.
 

.github/workflows/copilot-setup-steps.yml

@@ -111,7 +111,7 @@ jobs:
       # ========================================================================
 
       - name: Ensure crystal runs without error
-        run: poetry run crystal --help
+        run: poetry run crystal --version
 
       - name: Run non-UI tests
         run: poetry run python -m pytest