conformance: add the polygons and validity digest streams

[justinhwang]

Summary

Adds the two digest streams the suite was missing. Both change the shape of the digest files, so they land together and before the format is carried anywhere else.

polygons, a thirteenth per-cell stream in digests/resolutions.jsonl and digests/baseCells.jsonl. For every cell at resolutions 0 through 2: the boundary scaled about its center by 0.8 and by 1.2, exactly as the regions group scales it, filled two resolutions finer by polygonToCellsExperimental in center, full, overlapping and overlappingBbox, eight sets per line. The key is present only on rows at or below resolution 2, so finer rows keep twelve keys. That is 5,882 cells and 47,056 fills. Resolution 3 would be seven times that for the same code paths and measured about 25 seconds per run in the Go runner, so it was left out.

validity, in a new digests/patterns.jsonl. A stream of 64-bit words that are mostly not cells, one line each with isValidCell, isValidIndex, isValidDirectedEdge and isValidVertex. Uniform random words are invalid on the mode bits alone almost every time, so seven draws in eight take a valid cell and disturb one field: mode, reserved bits, resolution, base cell, one digit, the high bit, or the mode set to edge or vertex with random reserved bits. That is where validators that stop at the mode and resolution are caught. Digests are recorded at 100,000, 1,000,000 and 10,000,000 patterns of the same stream, so a runner computes all three in one pass. The Go runner checks to one million by default; H3_CONFORMANCE_PATTERNS_MAXCOUNT raises it.

The README specifies both: the line formats, the scaling, and the draw order of every pattern kind.

Results

Both streams pass in pure Go on the first run against the C-generated digests.

Check	Time (no race)
Validity stream, all three tiers to ten million patterns	1.8 s
Resolution and base-cell digests to res 3, with polygons to res 2	4.4 s
Whole conformance package under -race	27 s

Every file outside digests/ is byte-identical to before; the manifest changes only in the two digest entries and the new patterns entry.

Test plan

• go test -count=1 -race -cover ./x/h3go/conformance/ passes with 100% coverage
• H3_CONFORMANCE_PATTERNS_MAXCOUNT=10000000 passes
• golangci-lint run ./x/h3go/conformance/... clean
• Regenerated with generate.sh; every file outside digests/ is byte-identical

🤖 Generated with Claude Code

[coveralls]

Coverage Report for CI Build 37258179900

Coverage remained the same at 100.0%

Details

• Coverage remained the same as the base build.
• Patch coverage: 1 of 1 lines across 1 file are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	4539
Covered Lines:	4539
Line Coverage:	100.0%
Coverage Strength:	2694571.53 hits per line

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💛 - Coveralls