lib: refactor internal webidl converters

[panva]

Rework lib/internal/webidl.js into a documented shared converter module that follows the Web IDL conversion algorithms more closely.

Improvements:

• Add documented converters and helper factories for primitive values, dictionaries, enums, sequences, interfaces, required arguments, integers, Uint8Array, and BufferSource.
• Move WebCrypto onto the shared converters, while keeping compatibility wrappers for its existing BufferSource and BigInteger behavior.
• Use shared converters from Blob, Performance, Web Locks, and structured clone option handling.
• Add benchmarks for ConvertToInt and WebCrypto Web IDL converter hot paths.
• Add focused tests for core converters, WebCrypto converters, integer conversion, and buffer source behavior.

Fixes:

• Make the shared BufferSource and Uint8Array converters reject resizable ArrayBuffer and growable SharedArrayBuffer backing stores unless explicitly allowed. WebCrypto preserves its legacy resizable backing-store behavior through compatibility wrappers until a semver-major follow-up can opt in to the stricter behavior.
• Use Web IDL ToNumber and ToString behavior for BigInt, Symbol, and object primitive conversion.
• Use exact BigInt modulo for 64-bit ConvertToInt wrapping and document the final Number approximation behavior.
• Normalize mathematical modulo results to +0 where Web IDL requires it.
• Process inherited dictionaries in least-derived to most-derived order, sorting members only within each dictionary level.
• Use IteratorComplete truthiness for sequence conversion.
• Cover detached buffers, resizable-backed views, growable-backed views, cross-realm buffer sources, mutation-after-call behavior, inherited dictionary member order, and sequence iterator completion behavior.

Benchmark(s)

• lib: refactor internal webidl converters #62979 (comment)
• lib: refactor internal webidl converters #62979 (comment)

[nodejs-github-bot]

Review requested:

• @nodejs/crypto
• @nodejs/web-standards

[codecov]

Codecov Report

❌ Patch coverage is 99.32886% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.69%. Comparing base (21436f0) to head (0cfebb7).
⚠️ Report is 19 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/internal/crypto/webidl.js	98.92%	5 Missing ⚠️
lib/internal/webidl.js	99.53%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #62979      +/-   ##
==========================================
+ Coverage   89.66%   89.69%   +0.03%     
==========================================
  Files         706      707       +1     
  Lines      219391   219950     +559     
  Branches    42068    42111      +43     
==========================================
+ Hits       196712   197280     +568     
+ Misses      14578    14567      -11     
- Partials     8101     8103       +2     

Files with missing lines	Coverage Δ
lib/internal/blob.js	99.44% <100.00%> (+<0.01%)	⬆️
lib/internal/locks.js	94.39% <100.00%> (ø)
lib/internal/perf/performance.js	93.54% <100.00%> (+0.05%)	⬆️
lib/internal/worker/js_transferable.js	98.56% <100.00%> (+0.01%)	⬆️
lib/internal/webidl.js	99.43% <99.53%> (+2.70%)	⬆️
lib/internal/crypto/webidl.js	99.33% <98.92%> (+0.95%)	⬆️

... and 42 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[panva]

i'm nearing the end of what i can optimize on the hot paths, just one more fixup then i'll do a final benchmark

[panva]

Benchmark CI: https://ci.nodejs.org/view/Node.js%20benchmark/job/benchmark-node-micro-benchmarks/1842

                                                                                         confidence improvement accuracy (*)     (**)    (***)
misc/webcrypto-webidl.js n=1000000 op='normalizeAlgorithm-dict'                                 ***     80.70 %       ±1.24%   ±1.66%   ±2.16%
misc/webcrypto-webidl.js n=1000000 op='normalizeAlgorithm-string'                               ***     57.96 %       ±0.77%   ±1.03%   ±1.36%
misc/webcrypto-webidl.js n=1000000 op='webidl-algorithm-identifier-object'                              -0.98 %       ±3.94%   ±5.27%   ±6.91%
misc/webcrypto-webidl.js n=1000000 op='webidl-algorithm-identifier-string'                              -5.16 %       ±5.97%   ±8.01%  ±10.55%
misc/webcrypto-webidl.js n=1000000 op='webidl-dict-enforce-range'                               ***     13.85 %       ±1.02%   ±1.37%   ±1.81%
misc/webcrypto-webidl.js n=1000000 op='webidl-dict-ensure-sha'                                  ***    170.12 %       ±1.38%   ±1.85%   ±2.45%
misc/webcrypto-webidl.js n=1000000 op='webidl-dict-null'                                        ***    -62.11 %       ±5.31%   ±7.13%   ±9.43%
misc/webcrypto-webidl.js n=1000000 op='webidl-dict'                                             ***     15.13 %       ±0.62%   ±0.83%   ±1.08%
misc/webidl-buffer-source.js n=1000000 input='arraybuffer'                                        *     -4.96 %       ±3.99%   ±5.32%   ±6.92%
misc/webidl-buffer-source.js n=1000000 input='bigint64array'                                             1.45 %       ±5.46%   ±7.27%   ±9.47%
misc/webidl-buffer-source.js n=1000000 input='biguint64array'                                            1.86 %       ±4.37%   ±5.83%   ±7.60%
misc/webidl-buffer-source.js n=1000000 input='buffer'                                                   -0.12 %       ±3.25%   ±4.32%   ±5.63%
misc/webidl-buffer-source.js n=1000000 input='dataview'                                         ***     -8.94 %       ±3.94%   ±5.24%   ±6.83%
misc/webidl-buffer-source.js n=1000000 input='float16array'                                              1.28 %       ±3.69%   ±4.92%   ±6.41%
misc/webidl-buffer-source.js n=1000000 input='float32array'                                             -1.30 %       ±3.71%   ±4.93%   ±6.42%
misc/webidl-buffer-source.js n=1000000 input='float64array'                                              1.09 %       ±5.30%   ±7.05%   ±9.17%
misc/webidl-buffer-source.js n=1000000 input='int16array'                                                0.21 %       ±5.04%   ±6.74%   ±8.86%
misc/webidl-buffer-source.js n=1000000 input='int32array'                                               -1.84 %       ±4.47%   ±5.95%   ±7.76%
misc/webidl-buffer-source.js n=1000000 input='int8array'                                                 1.56 %       ±3.78%   ±5.03%   ±6.55%
misc/webidl-buffer-source.js n=1000000 input='uint16array'                                               1.07 %       ±4.19%   ±5.59%   ±7.29%
misc/webidl-buffer-source.js n=1000000 input='uint32array'                                               0.09 %       ±5.04%   ±6.73%   ±8.79%
misc/webidl-buffer-source.js n=1000000 input='uint8array'                                               -1.34 %       ±5.15%   ±6.87%   ±8.98%
misc/webidl-buffer-source.js n=1000000 input='uint8clampedarray'                                        -2.39 %       ±3.98%   ±5.30%   ±6.91%
misc/webidl-convert-to-int.js n=1000000 input='clamp' converter='byte'                          ***   2364.33 %      ±37.30%  ±50.27%  ±66.73%
misc/webidl-convert-to-int.js n=1000000 input='clamp' converter='long long'                     ***    910.48 %      ±24.25%  ±32.68%  ±43.38%
misc/webidl-convert-to-int.js n=1000000 input='clamp' converter='octet'                         ***   1871.53 %      ±36.50%  ±49.19%  ±65.31%
misc/webidl-convert-to-int.js n=1000000 input='clamp' converter='unsigned long'                 ***    697.51 %      ±12.22%  ±16.47%  ±21.85%
misc/webidl-convert-to-int.js n=1000000 input='clamp' converter='unsigned short'                ***    680.33 %      ±13.68%  ±18.43%  ±24.47%
misc/webidl-convert-to-int.js n=1000000 input='enforce-range' converter='byte'                  ***    789.35 %      ±33.50%  ±45.15%  ±59.93%
misc/webidl-convert-to-int.js n=1000000 input='enforce-range' converter='long long'             ***    817.08 %      ±16.35%  ±22.03%  ±29.24%
misc/webidl-convert-to-int.js n=1000000 input='enforce-range' converter='octet'                 ***    267.04 %       ±5.89%   ±7.86%  ±10.27%
misc/webidl-convert-to-int.js n=1000000 input='enforce-range' converter='unsigned long'         ***    239.33 %       ±5.71%   ±7.63%   ±9.99%
misc/webidl-convert-to-int.js n=1000000 input='enforce-range' converter='unsigned short'        ***    228.15 %       ±8.52%  ±11.40%  ±14.96%
misc/webidl-convert-to-int.js n=1000000 input='fractional' converter='byte'                     ***   3303.13 %     ±155.26% ±209.25% ±277.80%
misc/webidl-convert-to-int.js n=1000000 input='fractional' converter='long long'                ***   3554.14 %     ±130.83% ±176.32% ±234.09%
misc/webidl-convert-to-int.js n=1000000 input='fractional' converter='octet'                    ***   2316.22 %      ±29.23%  ±39.39%  ±52.29%
misc/webidl-convert-to-int.js n=1000000 input='fractional' converter='unsigned long'            ***   2253.50 %      ±46.15%  ±62.20%  ±82.57%
misc/webidl-convert-to-int.js n=1000000 input='fractional' converter='unsigned short'           ***   2028.85 %      ±43.02%  ±57.98%  ±76.98%
misc/webidl-convert-to-int.js n=1000000 input='integer' converter='byte'                        ***   3904.02 %      ±26.77%  ±36.07%  ±47.89%
misc/webidl-convert-to-int.js n=1000000 input='integer' converter='long long'                   ***   4202.53 %      ±39.36%  ±53.04%  ±70.42%
misc/webidl-convert-to-int.js n=1000000 input='integer' converter='octet'                       ***   2569.17 %      ±50.27%  ±67.75%  ±89.95%
misc/webidl-convert-to-int.js n=1000000 input='integer' converter='unsigned long'               ***   2550.93 %      ±39.27%  ±52.93%  ±70.27%
misc/webidl-convert-to-int.js n=1000000 input='integer' converter='unsigned short'              ***   2447.31 %      ±33.04%  ±44.52%  ±59.11%
misc/webidl-convert-to-int.js n=1000000 input='object' converter='byte'                         ***    662.03 %      ±17.80%  ±23.99%  ±31.85%
misc/webidl-convert-to-int.js n=1000000 input='object' converter='long long'                    ***    668.98 %      ±14.18%  ±19.11%  ±25.37%
misc/webidl-convert-to-int.js n=1000000 input='object' converter='octet'                        ***    408.93 %       ±8.99%  ±12.11%  ±16.07%
misc/webidl-convert-to-int.js n=1000000 input='object' converter='unsigned long'                ***    403.11 %       ±7.30%   ±9.83%  ±13.04%
misc/webidl-convert-to-int.js n=1000000 input='object' converter='unsigned short'               ***    400.87 %       ±6.88%   ±9.27%  ±12.30%
misc/webidl-convert-to-int.js n=1000000 input='wrap' converter='byte'                           ***    736.95 %      ±29.07%  ±39.18%  ±52.01%
misc/webidl-convert-to-int.js n=1000000 input='wrap' converter='long long'                      ***    217.47 %       ±4.32%   ±5.82%   ±7.72%
misc/webidl-convert-to-int.js n=1000000 input='wrap' converter='octet'                          ***    481.05 %      ±13.79%  ±18.58%  ±24.66%
misc/webidl-convert-to-int.js n=1000000 input='wrap' converter='unsigned long'                  ***    473.76 %      ±20.60%  ±27.77%  ±36.86%
misc/webidl-convert-to-int.js n=1000000 input='wrap' converter='unsigned short'                 ***    491.65 %      ±27.24%  ±36.71%  ±48.74%

Be aware that when doing many comparisons the risk of a false-positive
result increases. In this case, there are 53 comparisons, you can thus
expect the following amount of false-positive results:
  2.65 false positives, when considering a   5% risk acceptance (*, **, ***),
  0.53 false positives, when considering a   1% risk acceptance (**, ***),
  0.05 false positives, when considering a 0.1% risk acceptance (***)

[panva]

(just a rebase, no changes)