feat(ast): AstKind::debug_name()

[DonIsaac]

Adds AstKind::debug_name(), which returns the name of an AstKind struct with a few minor details as applicable. I intentionally did not make AstKind implement Display, as this method returns minimal information. Additionally, this method only exists in debug builds. I've hidden it behind a #[cfg(debug_assertions)], so it won't affect release builds.

This code was extracted from #642, where it as created while debugging iteration over ancestor nodes. I figured it belonged in its own PR and may be useful to other devs.

[github-actions]

Benchmark Results

Linux

group                            main                                   pr
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minifier/antd.js                 1.00    278.5±3.06ms    22.9 MB/sec    1.00    279.4±3.31ms    22.8 MB/sec
minifier/react.development.js    1.00      3.1±0.03ms    22.4 MB/sec    1.00      3.1±0.02ms    22.4 MB/sec
minifier/typescript.js           1.00    468.9±4.32ms    22.0 MB/sec    1.01    472.5±4.23ms    21.8 MB/sec
minifier/vue.js                  1.00     19.2±0.43ms    17.0 MB/sec    1.00     19.2±0.45ms    17.0 MB/sec
parser/antd.js                   1.00     88.7±0.78ms    71.9 MB/sec    1.01     89.5±1.30ms    71.3 MB/sec
parser/react.development.js      1.00  1007.3±12.32µs    68.3 MB/sec    1.00  1004.7±13.89µs    68.5 MB/sec
parser/typescript.js             1.01    153.5±1.56ms    67.2 MB/sec    1.00    151.8±1.24ms    68.0 MB/sec
parser/vue.js                    1.01      6.3±0.04ms    51.8 MB/sec    1.00      6.3±0.04ms    52.1 MB/sec
semantic/antd.js                 1.00     87.7±4.07ms    72.7 MB/sec    1.02     89.1±4.32ms    71.5 MB/sec
semantic/react.development.js    1.01  1023.7±28.95µs    67.2 MB/sec    1.00  1008.9±23.73µs    68.2 MB/sec
semantic/typescript.js           1.00    193.3±8.11ms    53.4 MB/sec    1.02    196.2±9.35ms    52.6 MB/sec
semantic/vue.js                  1.01      6.8±0.26ms    48.2 MB/sec    1.00      6.7±0.21ms    48.7 MB/sec

Windows

group                            main                                   pr
-----                            ----                                   --
minifier/antd.js                 1.06   351.8±12.88ms    18.1 MB/sec    1.00    330.8±8.23ms    19.3 MB/sec
minifier/react.development.js    1.00      3.3±0.05ms    20.8 MB/sec    1.00      3.3±0.04ms    20.8 MB/sec
minifier/typescript.js           1.01   526.9±14.90ms    19.6 MB/sec    1.00   521.3±13.44ms    19.8 MB/sec
minifier/vue.js                  1.00     19.9±0.58ms    16.4 MB/sec    1.00     19.8±0.36ms    16.5 MB/sec
parser/antd.js                   1.01     86.1±2.91ms    74.1 MB/sec    1.00     84.9±1.82ms    75.1 MB/sec
parser/react.development.js      1.00   941.3±16.72µs    73.1 MB/sec    1.00   940.4±16.43µs    73.2 MB/sec
parser/typescript.js             1.02    148.6±2.94ms    69.4 MB/sec    1.00    145.3±2.34ms    71.0 MB/sec
parser/vue.js                    1.00      5.8±0.07ms    56.4 MB/sec    1.02      5.9±0.08ms    55.6 MB/sec
semantic/antd.js                 1.02    103.5±6.22ms    61.6 MB/sec    1.00    101.4±5.94ms    62.9 MB/sec
semantic/react.development.js    1.00  1137.4±44.65µs    60.5 MB/sec    1.00  1140.6±32.03µs    60.3 MB/sec
semantic/typescript.js           1.02   220.8±15.54ms    46.7 MB/sec    1.00   216.0±17.95ms    47.8 MB/sec
semantic/vue.js                  1.04      7.5±0.28ms    43.2 MB/sec    1.00      7.3±0.18ms    44.8 MB/sec