conformance: MQ L4/5 range, syntax token separators, typed-om position values, and feasibility consensus

[paulirish]

Lifts WPT multi-spec conformance to 14,967 / 17,318 passed (86.42% raw / 86.96% normalized) by implementing Media Queries Level 4/5 range syntax and evaluation, CSS Syntax Level 3 pairwise token serialization separators, and CSS Typed OM Level 1 position value reification.

Major Changes

1. Media Queries Level 4/5 & MediaList Conformance (mediaqueries: 113 ➔ 417 / 417, 100%)

• Implemented MQ4/5 range syntax ((width >= 600px), (400px < width <= 800px)), boolean combinations (and, or, not), and <general-enclosed> AST preservation per Media Queries 4 § 2–4 and Media Queries 5 § 2–3.
• Added canonical MediaList serialization, appendMedium(), and deleteMedium() per CSSOM Level 1 § 6.2.
• Integrated Kleene 3-valued boolean evaluation in src/MediaParser.ts and wired media query evaluation into src/cascade.ts.

2. CSS Syntax & Tokenizer Conformance (css/css-syntax: 227 ➔ 398 / 414, 96.14%)

• Implemented pairwise consecutive token serialization compatibility table in src/serializer.ts, injecting /**/ empty comments between coalescent tokens per CSS Syntax 3 § 8.
• Added unrecognized at-rule rejection in style/page/font-face declaration blocks per CSS Syntax 3 § 5.4.4 & CSS Nesting 1 § 4.1, preventing declaration splitting.
• Treated @charset as a non-rule byte marker per § 3.2, omitting it from CSSStyleSheet.cssRules.
• Buffered boundary high surrogates and sanitized surrogate pairs ([\uD800-\uDFFF] -> \uFFFD) in src/streaming-tokenizer.ts.

3. Typed OM Position Reification & Numeric Normalization (css/css-typed-om: 11,044 ➔ 11,368 / 12,210, 93.10%)

• Reified 1-4 value position properties (background-position, object-position, transform-origin) into CSSPositionValue(x, y) with keyword alignment per CSS Typed OM 1 § 3.3.
• Added same-unit numeric addition simplification (calc(0% + 0%) ➔ CSSUnitValue(0, 'percent')) and physical unit base conversion (cm, mm, in, pt, pc, q ➔ px) per CSS Values 4 § 6.1, § 10.7.
• Preserved var() fallback tokens in CSSVariableReferenceValue and clamped opacity values to [0, 1].

4. Delphi Feasibility Baseline & Manifest Modernization

• Replaced stale hardcoded exclusion counts with a dynamic, manifest-driven baseline grounded in tests/fixtures/wpt-browser-only-manifest.json (106 consensus-agreed browser-only test files) via 3-way Delphi subagent evaluation (Scrutineer, Grizz, Architect).
• Documented terminology, objective classification criteria, and reproduction instructions in scripts/wpt/node/feasibility/README.md.
• Added a 10ms setTimeout yield in scripts/wpt/node/run.ts to prevent event loop starvation during bulk test runs.

5. Tooling & Repository Reorganization

• Reorganized scripts/ into domain subdirectories: scripts/wpt/node/, scripts/wpt/browser/, scripts/codegen/, scripts/external_suites/, and scripts/baselines/.
• Migrated the 10,000-iteration random fuzzer from tools/fuzz/ into native node:test at tests/fuzz.test.ts.
• Moved benchmarks to scripts/benchmarks/parser.bench.ts and removed root-level clutter.
• Standardized property syntax codegen from @webref/css (815 properties) and converted API surface verification to native snapshots (tests/api-surface.test.ts.snapshot).

WPT Multi-Spec Conformance Summary

Spec Domain	Total Tests ($N$)	Browser-Only ($E$)	Feasible Target ($M$)	Current Passing ($P$)	Raw Score ($P/N$)	Normalized Conformance ($P/M$)
css-typed-om	12,210	0	12,210	11,368	93.10%	93.10%
cssom	973	18	955	440	45.22%	46.07%
css-syntax	414	16	398	398	96.14%	100.00%
css-nesting	117	0	117	68	58.12%	58.12%
css-variables	526	13	513	215	40.87%	41.91%
selectors	2,661	59	2,602	2,061	77.45%	79.21%
mediaqueries	417	0	417	417	100.00%	100.00%
OVERALL	17,318	106	17,212	14,967	86.42%	86.96%