test(processor): git-mode whole-file and line-range cases

internal/processor/testdata/git_range.js

@@ -0,0 +1,2 @@
+a(); // one
+b(); // two

internal/processor/testdata/git_range.js.golden

@@ -0,0 +1,2 @@
+a();
+b(); // two

internal/processor/testdata/git_whole.py

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+# gone
+x = 1  # inline

internal/processor/testdata/git_whole.py.golden

@@ -0,0 +1 @@
+x = 1