docs: h5rs in the changelog and the crate table

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

CHANGELOG.md

@@ -112,6 +112,50 @@
   `quantized_index = false`, or pass `create --f32-index` to the CLI, to opt
   out. The CLI's `--quantized-index` is still accepted but is now a no-op.
 
+### Tools
+- New crate **`clawhdf5-tools`** with the binary **`h5rs`**: HDF5
+  command-line tools without libhdf5, built only on the `clawhdf5` facade
+  and `clawhdf5-format` (no C, so it also builds as a static musl binary).
+  - `h5rs ls [-r] [-v] FILE[/path]` lists objects like h5ls (its first two
+    columns are h5ls's text on the test files) plus the datatype; `-v` adds
+    address, link count, layout and chunk index, chunk size, storage,
+    filters, datatype and attributes.
+  - `h5rs dump [--json] [-A] [-p] [-d PATH] FILE` prints DDL text that is
+    byte-identical to h5dump 1.14.6's on the test files (all layouts and
+    chunk indexes, v1/v2 groups, compound, enum, strings, links, named
+    types, attributes), or JSON in the HDF Group's hdf5-json layout (schema
+    in the crate README).
+  - `h5rs stat FILE` reports h5stat's object, link, rank, layout, filter,
+    attribute, raw-data and file-size figures (equal to h5stat's on the test
+    files); metadata space is one figure, not broken down.
+  - `h5rs diff [-r] [-q] [-d D] [-p R] A B [OBJ1 [OBJ2]]` compares objects,
+    kinds, datatypes, shapes, attributes, values and link targets; exit
+    status 0/1/2 as h5diff's. Objects that cannot be compared count as a
+    difference (h5diff exits 0 for them), and NaN equals NaN.
+  - `h5rs check [--data] FILE` is a structural validator: it walks every
+    object, parses every header message, verifies the checksums of every
+    version 2+ structure it meets (superblock, object headers and
+    continuation chunks, v2 B-tree nodes, fractal heap headers and — which
+    the library's reads do not — every direct and indirect heap block, and
+    extensible/fixed array chunk indexes), checks each chunk index against
+    its dataset (aligned, in-extent, unique, plausibly sized chunks), and
+    that raw data lies inside the file without overlaps. Every problem is
+    printed with its address; exit 1 when there are any. libhdf5's h5check
+    reads only the 1.8 format. On the conformance corpus it passes all 418
+    files that both clawhdf5 and h5py read in full, and flags 149 of the
+    180 CVE reproducers.
+  - Values over `--max-bytes` (default 1 GiB) are reported instead of read;
+    a panic is caught and reported as an internal error (exit 3).
+    `scripts/h5rs-fuzz.sh` runs every subcommand over a corpus (default the
+    CVE reproducers, optionally with byte-flipped copies) with overflow
+    checks, a timeout and a memory limit, and fails on any panic, crash or
+    hang; `scripts/h5rs-check-ok-files.sh` runs `check --data` over the
+    fully-read conformance files.
+  - Because the library does not verify fractal heap block checksums when
+    it reads a dense group's links or dense attributes, `h5rs` verifies a
+    heap's blocks before reading from it and refuses a damaged one, as
+    libhdf5 does, instead of printing what the damaged block holds.
+
 ### Signing
 - `clawhdf5-agent`: **Ed25519-signed checkpoints** — the README's
   "cryptographically verifiable memory", now true. With