docs: fact-check the refreshed documentation against its sources

Numbers, API names, feature defaults and PR references checked against
CONFORMANCE.md, BENCHMARKS.md, CHANGELOG.md, the code and git history.

- int8 index figures (1.74x memory, 1.63x QPS) carry the dates git gives
  them (2026-09-19/20, machine not recorded, not re-run) instead of none;
  the Pi 5 1.18x carries 2026-09-21.
- BENCHMARKS headline: the libhdf5 chunked-write figure is the newest
  measurement (35x, 2026-09-23), not 45.3x (2026-08-03).
- Conformance counts follow the 2026-09-28 run (1 our-error, 2 ref-bug)
  in conformance/README.md, ROADMAP.md and CLAUDE.md, with a pointer to
  the bad_nbit_parms_walk.h5 flip.
- README: LZ4 is opt-in; the browser refuses reference/opaque/bitfield/
  time datasets too; zlib-rs byte-identity scoped to what was measured;
  macOS default links the system libz for inflate.
- Crate READMEs: system-zlib-decompress does something (macOS), SweepDetector
  lives in prefetch, checkpoint after more than 500 WAL entries, NetCDF-4
  unlimited-dimension size warning.
- agent-memory.md: string-dataset compression threshold, agents-md prints
  Markdown, float16 file sizes linked to their study.
- known-issues.md: contiguous selection reads, 1.21x vs h5py threads.
- docs/README.md, USE_CASES.md, ROADMAP.md, CLAUDE.md: range-read
  milestones M0-M5 and PRs #17-#19, missing README rows, CLI keygen/verify,
  dated figures, fast-math is not BLAS.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

CLAUDE.md

@@ -72,7 +72,7 @@ and `docs/design/swmr.md`, `CHANGELOG.md` (full detail of every fix).
 ## HDF5 library: invariants and gotchas
 
 - **Remote/range reads** (`docs/design/range-reads.md`, M0-M5 merged in PRs
-  #17-#21): every format-crate read path goes through `Storage`
+  #17-#19, M4 listing costs cut in #21): every format-crate read path goes through `Storage`
   (`read_at`/`read_ranges`/`hint`). `File::open_storage` takes any
   `Storage`; `clawhdf5_remote::open_url` wraps HTTP (`HttpStorage`, ureq) or
   `ObjectStoreStorage` in `BlockCache` (1 MiB blocks, LRU budget, in-flight
@@ -197,8 +197,8 @@ bash scripts/ci-test.sh          # everything CI runs (see below)
   `cargo bench --no-run`; `check-nostd.sh`; an optional fuzz smoke run
   (`CLAWHDF5_FUZZ_SECONDS`).
 - **`ci.yml` `test-arm64`** (`linux_arm64`; `vision-01` host mode,
-  `vision-02` Docker — steps must work in both): clippy and tests of
-  `clawhdf5-accel`, `-ann`, `-format`; the only place the NEON kernels build.
+  `vision-02` Docker — steps must work in both): clippy of
+  `clawhdf5-accel`, tests of `-accel`, `-ann`, `-format`; the only place the NEON kernels build.
 - **`conformance.yml`** (nightly 03:17 UTC and manual): probe unit tests,
   `conformance/test_ref.py`, then `conformance/run.sh` (gate:
   `conformance/check.py` against `baseline.json`).
@@ -214,7 +214,7 @@ frozen at 0.6.1).
 CLAWHDF5_PYTHON=.venv/bin/python bash conformance/run.sh --no-fetch   # writes CONFORMANCE.md
 ```
 Reads 697 files of eight pinned corpora with clawhdf5 and h5py and compares
-them object by object (602 ok as of 2026-09-27). `CONFORMANCE.md` is
+them object by object (602 ok in the run of 2026-09-28). `CONFORMANCE.md` is
 generated — never hand-edit it (its wording lives in `conformance/report.py`).
 Use `--update-baseline` only after an intended change in results.
 `CONFORMANCE_CACHE` points at an existing corpus cache (`conformance/.cache`,
@@ -261,7 +261,7 @@ python -m pytest crates/clawhdf5-py/tests      # compares with h5py; editing tes
 ### CLI
 ```bash
 cargo run -p clawhdf5-cli -- --help
-# create, save, search, recall, stats, flush-wal, agents-md, export, snapshot
+# create, save, search, recall, stats, flush-wal, agents-md, export, snapshot, keygen, verify
 ```
 
 ## Integration