[buildifier] Only the first unusued loaded symbol is marked as autofixable

When a file has multiple unused symbols in a single load statement, only the first unused symbol emits a warning with autoFixable: true. Subsequent symbols are marked as "actionable", but not "autoFixable". However, if you run buildifier with -lint fix, it will remove both unused symbols. This is annoying when writing linter wrappers as I can't tell which things from --lint warn will be handled for me (so I don't need to show them to the user) on a subsequent run with --lint fix.

Simple repro here on v8.5.1:

$ .local/bin/buildifier --version
buildifier version: 8.5.1
buildifier scm revision: v8.5.1
$  echo -e 'load("foo.bzl", "bar", "baz", "quz")\nbar(name="target")' | .local/bin/buildifier -lint warn -mode check -format json -path BUILD.bazel | jq '.files[0]'
{
  "filename": "BUILD.bazel",
  "formatted": false,
  "valid": true,
  "warnings": [
    {
      "start": {
        "line": 1,
        "column": 25
      },
      "end": {
        "line": 1,
        "column": 28
      },
      "category": "load",
      "actionable": true,
      "autoFixable": true,
      "message": "Loaded symbol \"baz\" is unused. Please remove it.\nTo disable the warning, add '@unused' in a comment.",
      "url": "https://github.com/bazelbuild/buildtools/blob/main/WARNINGS.md#load"
    },
    {
      "start": {
        "line": 1,
        "column": 32
      },
      "end": {
        "line": 1,
        "column": 35
      },
      "category": "load",
      "actionable": true,
      "autoFixable": false,
      "message": "Loaded symbol \"quz\" is unused. Please remove it.\nTo disable the warning, add '@unused' in a comment.",
      "url": "https://github.com/bazelbuild/buildtools/blob/main/WARNINGS.md#load"
    }
  ]
}
$ { PROG=$(echo -e 'load("foo.bzl", "bar", "baz", "quz")\nbar(name="target")'); diff -u <((echo "$PROG")) <((echo "$PROG" | .local/bin/buildifier -lint fix -path BUILD.bazel)); }
--- /dev/fd/63	2026-04-14 09:44:01
+++ /dev/fd/62	2026-04-14 09:44:01
@@ -1,2 +1,3 @@
-load("foo.bzl", "bar", "baz", "quz")
-bar(name="target")
+load("foo.bzl", "bar")
+
+bar(name = "target")

I'm guessing there's something to do with how multiple fixes on the same line are handled, but haven't dug into the buildifier code too much to verify where it's coming from .

Start with the buildifier CLI behavior shown for BUILD.bazel: reproduce the load statement with multiple unused symbols using -lint warn -mode check -format json, then compare it with -lint fix. Trace how the load warnings and fixes are generated; done means every unused symbol removed by -lint fix is reported with autoFixable: true by -lint warn.