feat(pm): isolate developer test environment from runtime extras

activate

@@ -18,15 +18,41 @@
 # install` and `hermes update` keep that check.
 # ============================================================================
 _HERMES_REPO="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+# Options: `--test-extras a,b` selects the test environment's runtime extras
+# (default: [all]); `--` ends options.
+# A bare `source ./activate` inherits the caller's positional parameters.
+# Ignore unrelated words so scripts with their own arguments can source it.
+_hermes_test_env="--test-environment"
+_hermes_expect_extras=""
+for _hermes_arg in "$@"; do
+    if [ -n "$_hermes_expect_extras" ]; then
+        _hermes_test_env="--test-environment=$_hermes_arg"
+        _hermes_expect_extras=""
+        continue
+    fi
+    case "$_hermes_arg" in
+        --) break ;;
+        --test-extras) _hermes_expect_extras=1 ;;
+        --test-extras=*) _hermes_test_env="--test-environment=${_hermes_arg#--test-extras=}" ;;
+        *) : ;;
+    esac
+done
+if [ -n "$_hermes_expect_extras" ]; then
+    printf '%s\n' 'activate: --test-extras needs a comma-separated list' >&2
+    unset _hermes_arg _hermes_test_env _hermes_expect_extras
+    return 2 2>/dev/null || exit 2
+fi
 # Setup runs in a child: failures must not exit or partially activate the
 # caller's shell, and activation must not republish launchers or shell config.
 if ! (
     unset PYTHONHOME PYTHONPATH VIRTUAL_ENV
-    bash "$_HERMES_REPO/setup-hermes.sh" --runtime-only
+    bash "$_HERMES_REPO/setup-hermes.sh" --runtime-only "$_hermes_test_env"
 ) >&2; then
     printf '%s\n' 'activate: setup failed; shell environment unchanged' >&2
+    unset _hermes_arg _hermes_test_env _hermes_expect_extras
     return 1 2>/dev/null || exit 1
 fi
+unset _hermes_arg _hermes_test_env _hermes_expect_extras
 
 # Guard against double-sourcing: venv activate precedent (re-activating is a
 # no-op re-save; we keep it idempotent by deactivating first). Key on the