spb/metrika Public

- sysuse command with bundled samples (sales: 200-firm x 5-year panel;
  mtcars) shipped as ZQEngine resources, generated by
  scripts/make_samples.R
- metrika-cli docs: static documentation site rendered from the shared
  command registry (docs/index.html, 38 commands, light/dark); CLI
  restructured with a default 'run' subcommand
- Metal point-sprite renderer (CLAUDE.md §7 pane 4): packed 12-byte
  vertices, unified-memory buffer written once, scroll-pan /
  pinch-zoom / double-click-reset touching only a 24-byte uniform;
  takes over scatter plots past 100k points (METRIKA_METAL_THRESHOLD
  override for tests); verified rendering 2,000,000 points in-app
- METRIKA_AUTORUN debug hook for headless app driving
- MARKETING_VERSION 1.0.0
- 116 kit tests + 4 UI tests green

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

- PhiloxStream in ZQGPU: sequential variate stream over a dedicated
  counter block (bit 62 + per-stream 2^48 words, disjoint from bootstrap
  and permutation streams); Box-Muller normals, Marsaglia-Tsang gammas
  (moments verified against theory at 200k draws)
- ZQBayesianRegression: semi-conjugate Gibbs with Stata bayes default
  priors (coefficients N(0, 10000), variance InvGamma(.01, .01)); exact
  full conditionals via dense Cholesky; posterior mean/sd and
  equal-tailed 95% credible intervals; ZQStats now depends on ZQGPU for
  the shared RNG
- engine: 'bayes [, mcmcsize() burnin() seed() normalprior()]: reg …'
  with reproducible chains; manual entry included
- validation: with diffuse priors the posterior reproduces OLS (mean
  within 5% of a posterior SD, sd ratio in [0.9, 1.15], CrI brackets the
  estimate, sigma recovers the DGP); tight priors shrink toward zero;
  chains bit-reproducible per seed
- 111 tests green (swift test and xcodebuild with GPU suites)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

- mlx-swift dependency in ZQGPU (the only module allowed to import MLX)
- Philox4x32-10 as vectorized MLX uint64 ops with the reference key
  schedule: GPU resample indices are bit-identical to the CPU generator
  (asserted per replicate) — the §5 reproducibility contract
- batched gather + float32 cross-products on GPU, float64 Cholesky solves
  on CPU (§5 hybrid); chunked to the memory budget
- conditioning: predictors standardized by fixed full-sample mean/scale
  (exact reparametrization) before forming X'X — raw data with an
  intercept lost 2-3 digits in float32
- MLX workaround: batched GEMM mis-accumulates small k x k outputs at
  batch >= 2 (~6e-4 rel, stride/fusion-independent); X'X is built one
  column at a time through the exact (count,k,n)@(count,n,1) path, with
  regression tests pinning the behavior
- planner: gpuAvailable detected from actual metallib presence (SwiftPM
  CLI cannot compile Metal shaders - swift test skips GPU suites, the
  xcodebuild-built app and tests get the GPU); reps >= 500 dispatches
  bootstrap to .gpu
- engine: backend-aware bootstrap, drops singular resamples, output
  titled 'GPU batched' with gpu scalar
- 68 tests green under xcodebuild (66 + GPU suites under swift test skip)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

- MetrikaKit SPM package: ZQParser, ZQPlanner, ZQEngine, ZQData, ZQStats,
  ZQGPU, ZQGraphics, ZQPlugins (Swift 6, strict concurrency)
- ZQL parser: lexer, Pratt expressions, factor variables, prefix commands,
  column-cited errors with Levenshtein verb suggestions
- ZQData: DuckDB-backed load/save (parquet, csv, json, arrow)
- ZQStats: OLS via LAPACK QR, HC0-HC3 and cluster-robust SE, summarize,
  t/F distributions accurate in the far tails
- ZQGPU: Philox4x32-10 reference RNG, counter-addressable bootstrap
- ZQEngine: session actor with use/save/gen/replace/drop/keep/summarize/
  regress/count/list/graph/bootstrap/set seed/xtset/log
- SwiftUI app (xcodegen): console with history, variables sidebar,
  Swift Charts plots; sandboxed + hardened runtime entitlements
- Tests: 44 green (parser golden, R fixtures at 1e-10, Philox KAT,
  end-to-end engine); Tests/Fixtures/generate.R; Tests/Bench harness
- scripts: check_headers.sh + pre-commit hook, make_icns.sh, release.sh

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>