RFC#561 - {{lt}}, {{lte}}, {{gt}}, {{gte}} as keywords

[NullVoxPopuli]

Supersedes #21309

Add comparison helpers and register them as built-in keywords so they no longer need to be imported in strict-mode (gjs/gts) templates.

[github-actions]

📊 Package size report   0.2%↑

File	Before (Size / Brotli)	After (Size / Brotli)
dist/dev/packages/@ember/helper/index.js	18.7 kB / 4.9 kB	11%↑20.7 kB / 4%↑5.2 kB
dist/dev/packages/@ember/template-compiler/lib/plugins/auto-import-builtins.js	2.7 kB / 533 B	48%↑4 kB / 12%↑598 B
dist/dev/packages/shared-chunks/index-BGP1rw3B.js	199.2 kB / 43.7 kB	-68.3%↓63.1 kB / -71.3%↓12.6 kB
dist/dev/packages/shared-chunks/neq-BnthnWq8.js	3.2 kB / 1 kB	34%↑4.2 kB / 10%↑1.1 kB
dist/prod/packages/@ember/helper/index.js	18.6 kB / 4.9 kB	11%↑20.6 kB / 5%↑5.1 kB
dist/prod/packages/@ember/template-compiler/lib/plugins/auto-import-builtins.js	2.7 kB / 533 B	48%↑4 kB / 12%↑598 B
dist/prod/packages/shared-chunks/neq-DomVHPC_.js	2 kB / 705 B	26%↑2.6 kB / 10%↑779 B
types/stable/@ember/helper/index.d.ts	19.9 kB / 4.7 kB	13%↑22.5 kB / 5%↑4.9 kB
types/stable/@glimmer/runtime/index.d.ts	2.8 kB / 763 B	9%↑3 kB / 2%↑782 B
types/stable/@glimmer/runtime/lib/helpers/gt.d.ts	—	202 B / 128 B
types/stable/@glimmer/runtime/lib/helpers/gte.d.ts	—	214 B / 135 B
types/stable/@glimmer/runtime/lib/helpers/lt.d.ts	—	199 B / 129 B
types/stable/@glimmer/runtime/lib/helpers/lte.d.ts	—	211 B / 135 B
types/stable/index.d.ts	43 kB / 4 kB	0.6%↑43.2 kB / 0.1%↑4 kB
Total (Includes all files)	5.4 MB / 1.3 MB	0.2%↑5.4 MB / 0.1%↑1.3 MB
Tarball size	1.2 MB	0.2%↑1.2 MB

_{🤖 This report was automatically generated by pkg-size-action}

[bertdeblock]

Same question here as #21339 (comment).