增加G1零进给错误fixture验证

结论：新增 g1_zero_feed 负向 fixture，固定 G1 在 feed rate 为 0 时返回 INTERP_ERROR=5、输出 LinuxCNC 对应错误文本、不产生 STRAIGHT_FEED，且失败前不更新当前位置和 #5420/#5421/#5422。检查：git diff --check 通过；wasm-port/tests/native/verify_native_probes.sh 通过。

wasm-port/tests/fixtures/canon_errors/g1_zero_feed.expected

@@ -0,0 +1,9 @@
+execute_line_1=5
+error_text=Cannot do g1 with zero feed rate
+setup.current_x=0
+setup.current_y=0
+setup.current_z=0
+setup.parameter_5420=0
+setup.parameter_5421=0
+setup.parameter_5422=0
+absent=canon_event=STRAIGHT_FEED

wasm-port/tests/fixtures/gcode_errors/g1_zero_feed.ngc

@@ -0,0 +1 @@
+G1 X1.0

wasm-port/tests/native/verify_native_probes.sh

@@ -5,6 +5,8 @@ ROOT_DIR="$(cd "$(dirname "$0")/../.." && pwd)"
 BUILD_DIR="$ROOT_DIR/build/native"
 GCODE_FIXTURE_DIR="$ROOT_DIR/tests/fixtures/gcode"
 CANON_FIXTURE_DIR="$ROOT_DIR/tests/fixtures/canon"
+GCODE_ERROR_FIXTURE_DIR="$ROOT_DIR/tests/fixtures/gcode_errors"
+CANON_ERROR_FIXTURE_DIR="$ROOT_DIR/tests/fixtures/canon_errors"
 
 "$ROOT_DIR/tools/build_native_probes.sh"
 
@@ -77,4 +79,34 @@ for fixture in "$GCODE_FIXTURE_DIR"/*.ngc; do
   check_fixture_output "$fixture" "$expected" "$stdout_file"
 done
 
+for fixture in "$GCODE_ERROR_FIXTURE_DIR"/*.ngc; do
+  name="$(basename "$fixture" .ngc)"
+  expected="$CANON_ERROR_FIXTURE_DIR/$name.expected"
+  if [[ ! -f "$expected" ]]; then
+    echo "missing expected error fixture: $expected" >&2
+    exit 1
+  fi
+
+  stdout_file="$BUILD_DIR/linuxcnc_interp_minimal_harness.$name.stdout.log"
+  stderr_file="$BUILD_DIR/linuxcnc_interp_minimal_harness.$name.stderr.log"
+  "$BUILD_DIR/linuxcnc_interp_minimal_harness" "$fixture" \
+    >"$stdout_file" \
+    2>"$stderr_file"
+
+  while IFS= read -r expected_line; do
+    [[ -z "$expected_line" ]] && continue
+    if [[ "$expected_line" == absent=* ]]; then
+      forbidden="${expected_line#absent=}"
+      if grep -Fq "$forbidden" "$stdout_file"; then
+        echo "unexpected output in $stdout_file: $forbidden" >&2
+        exit 1
+      fi
+    elif [[ "$expected_line" == error_text=* ]]; then
+      grep -Fq "${expected_line#error_text=}" "$stderr_file"
+    else
+      grep -Fq "$expected_line" "$stdout_file"
+    fi
+  done < "$expected"
+done
+
 echo "native probe validation complete"