fix: remove unused assignment and import warnings in tests

docs/arch/mermaid/project.mmd

@@ -0,0 +1,42 @@
+graph TD
+    archlens_domain[archlens-domain]
+    archlens_application[archlens-application]
+    archlens[archlens]
+    subgraph Adapters
+        archlens_tree_sitter[archlens-tree-sitter]
+        archlens_walkdir[archlens-walkdir]
+        archlens_mermaid[archlens-mermaid]
+        archlens_ascii[archlens-ascii]
+        archlens_file_writer[archlens-file-writer]
+        archlens_stdout_writer[archlens-stdout-writer]
+        archlens_toml_config[archlens-toml-config]
+        archlens_cargo_workspace[archlens-cargo-workspace]
+        archlens_python_project[archlens-python-project]
+        archlens_d2[archlens-d2]
+        archlens_html[archlens-html]
+    end
+    archlens_application --> archlens_domain
+    archlens --> archlens_file_writer
+    archlens --> archlens_domain
+    archlens --> archlens_cargo_workspace
+    archlens --> archlens_d2
+    archlens --> archlens_html
+    archlens --> archlens_mermaid
+    archlens --> archlens_toml_config
+    archlens --> archlens_python_project
+    archlens --> archlens_ascii
+    archlens --> archlens_tree_sitter
+    archlens --> archlens_application
+    archlens --> archlens_walkdir
+    archlens --> archlens_stdout_writer
+    archlens_tree_sitter --> archlens_domain
+    archlens_walkdir --> archlens_domain
+    archlens_mermaid --> archlens_domain
+    archlens_ascii --> archlens_domain
+    archlens_file_writer --> archlens_domain
+    archlens_stdout_writer --> archlens_domain
+    archlens_toml_config --> archlens_domain
+    archlens_cargo_workspace --> archlens_domain
+    archlens_python_project --> archlens_domain
+    archlens_d2 --> archlens_domain
+    archlens_html --> archlens_domain