Fix review issues from commit 2a21d75

1. Rename goto_engineering_post_page/2 to visit_engineering_path/2 for
   better accuracy (used for both post pages and tag pages)

2. Simplify Makefile test target by removing explicit ecto.create and
   ecto.migrate commands (mix test handles migrations automatically)

3. Update blog_test.exs header comment to reflect actual changes made

4. Move Sandbox alias to top level in data_case.ex

app/Makefile

@@ -22,8 +22,6 @@ compile:
 # Run tests (requires PostgreSQL running on localhost:5432)
 # Note: If you don't have PostgreSQL, you can skip tests with `make check`
 test: deps compile
-	$(MISE_EXEC) mix ecto.create --quiet
-	$(MISE_EXEC) mix ecto.migrate --quiet
 	$(MISE_EXEC) mix test
 
 # Format code