chore: harden Taskfile common tasks

Taskfile.yml

@@ -24,13 +24,13 @@ vars:
   PYTHON_PROJECTS:
     sh: |
       find "$(git rev-parse --show-toplevel)" \
-        -path "*/.venv" -prune -o \
+        \( -path "*/.git" -o -path "*/.venv" -o -path "*/target" \) -prune -o \
         -name pyproject.toml -print | sort
   ACTIVE_PYTHON_PROJECTS:
     sh: |
       if [ "${TASK_INCLUDE_PYTHON:-}" = "1" ]; then
         find "$(git rev-parse --show-toplevel)" \
-          -path "*/.venv" -prune -o \
+          \( -path "*/.git" -o -path "*/.venv" -o -path "*/target" \) -prune -o \
           -name pyproject.toml -print | sort
       fi
   RUST_CORE_PACKAGES: >-
@@ -57,8 +57,12 @@ tasks:
           exit 1
         fi
         echo "{{.DETECTED_LANGUAGES}}"
-        if [ -n "{{.PYTHON_PROJECTS}}" ] && [ -z "{{.ACTIVE_PYTHON_PROJECTS}}" ]; then
-          echo "Python manifests detected; set TASK_INCLUDE_PYTHON=1 to include them in build/test/lint."
+        if [ -n "{{.PYTHON_PROJECTS}}" ]; then
+          echo "Python projects:"
+          printf '%s\n' "{{.PYTHON_PROJECTS}}"
+          if [ -z "{{.ACTIVE_PYTHON_PROJECTS}}" ]; then
+            echo "Set TASK_INCLUDE_PYTHON=1 to include Python projects in build/test/lint."
+          fi
         fi
 
   check:
@@ -113,7 +117,13 @@ tasks:
         if [ -n "{{.ACTIVE_PYTHON_PROJECTS}}" ]; then
           printf '%s\n' "{{.ACTIVE_PYTHON_PROJECTS}}" | while IFS= read -r pyproject; do
             project_dir="$(dirname "${pyproject}")"
-            (cd "${project_dir}" && uv run pytest)
+            if [ -d "${project_dir}/tests" ] || find "${project_dir}" \
+              -maxdepth 1 \
+              -name 'test_*.py' -print -quit | grep -q .; then
+              (cd "${project_dir}" && uv run --with pytest pytest)
+            else
+              echo "Skipping Python tests in ${project_dir}; no top-level tests found."
+            fi
           done
         elif [ -n "{{.PYTHON_PROJECTS}}" ]; then
           echo "Skipping Python tests by default; set TASK_INCLUDE_PYTHON=1 to include Python projects."
@@ -144,8 +154,8 @@ tasks:
             project_dir="$(dirname "${pyproject}")"
             (
               cd "${project_dir}" &&
-              uv run ruff check . &&
-              uv run ruff format --check .
+              uv run --with ruff ruff check . &&
+              uv run --with ruff ruff format --check .
             )
           done
         elif [ -n "{{.PYTHON_PROJECTS}}" ]; then