v0.2.1

Purely additive since 0.2.0 — no existing exported function, type, error
code, wire format, vector, or default behaviour changes. Existing tests and
vectors pass unmodified.

Added

• describeFilter(f) (.) — a plain, readonly public view of a
  MembershipFilter's metadata (fingerprintBits, filterType, keyed,
  padded, epoch, memberCountBand, segmentLength, segmentCount,
  arrayLength, byteLength, theoreticalFalsePositiveRate), and the
  FilterDescription type. Reveals nothing beyond what the serialized KFLT
  header already discloses (PROTOCOL.md §10).
• testMany(f, valuesHex) (.) — test many values against a filter in one
  call, with the exact same validation and semantics as calling
  testMembership on each value (PROTOCOL.md §10).
• verifyAndParseFilter's opts.strictlyNewerThan — an opt-in, stricter
  sibling of minEpoch that rejects a parsed filter whose epoch is not
  strictly greater than the given value, closing the same-epoch-replay gap
  minEpoch's non-strict < comparison leaves open for a caller who opts in
  (PROTOCOL.md §4.3). minEpoch's own behaviour is unchanged.
• New TesseraErrorCode values: TEST_VALUES_TYPE (testMany's
  non-array valuesHex), VERIFY_STRICTLY_NEWER_THAN_INVALID and
  VERIFY_EPOCH_NOT_NEWER (opts.strictlyNewerThan's validation and
  freshness-check failures).
• PROTOCOL.md §10 ("Introspection & bulk-test helpers") and §11 ("Evolution /
  versioning") — new sections; CONFORMANCE.md links §11.
• Dev tooling: fast-check property tests (build→serialize→parse round-trip
  and byte-identical re-serialization over random member sets sized 0–2000;
  testMany vs. the equivalent testMembership loop) and a structure-aware
  fast-check fuzz test for parseFilter that mutates individual header
  fields (boundary + random values), fingerprint bytes, and geometry-driven
  resizes, asserting every failure is a TesseraError; @vitest/coverage-v8
  and a test:coverage script (reporting only, no CI-failing thresholds); a
  bench script (scripts/bench.mjs, not run in CI or npm test) timing
  build/test/testMany/parse/sign/verify at 1k/100k/1M members.
• PROTOCOL.md corrections from an independent review of this pass: §11's
  "how a verifier rejects an unknown version" now distinguishes parseFilter
  (rejects at PARSE_UNSUPPORTED_VERSION, after bounds/magic) from
  verifyAndParseFilter (rejects almost all such blobs earlier, at
  VERIFY_SIGNATURE_OR_SIGNER_MISMATCH, since verifyFilterBlob never
  inspects format_version); §4.3 now states plainly that this kit does not
  enforce "one content per epoch," and gives usage guidance for
  strictlyNewerThan (an ordinary re-fetch of the current epoch throws
  VERIFY_EPOCH_NOT_NEWER — treat that as "no update," or use minEpoch
  for re-fetches instead); §9 and the TesseraErrorCode JSDoc now state the
  minor-vs-major stability policy explicitly (existing codes are fixed within
  a major version, new codes may be added in a minor one — don't write an
  exhaustive switch/Record over the union without a fallback).
• CI now runs the test matrix on Node 22 and 24 (was 22 only).

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Reproducible build: byte-identical output verified across two independent CI runners.

Artefact integrity

file:      forgesworn-tessera-kit-0.2.1.tgz
size:      276647 bytes
sha256:    70bd67be74d0ebe6f698ffa7d23c9df47ca312e73aaecf5c73cdb6379f555a6e
sha512-SLeid4PSZhuxGLbvbnP2eQVZxcvsdwqenzSsJh9krFGtu38F/rP4JuWHdmS8jaZ8ybvgtbJwQti0rWiR7P56Ig==

Verify against the registry tarball:

curl -sLO https://registry.npmjs.org/@forgesworn/tessera-kit/-/tessera-kit-0.2.1.tgz
shasum -a 256 tessera-kit-0.2.1.tgz