ci: wire up CI, fix no_std build, fix stale package names in scripts

- Add .gitea/workflows/ci.yml running scripts/ci-test.sh (fmt, clippy,
  test, no_std check) on push/PR to main.
- Fix stale rustyhdf5-py/rustyhdf5-format package names in
  ci-test.sh/check-nostd.sh, which had been silently no-op'ing those
  checks (cargo warns but doesn't fail on an unknown --exclude/-p
  target).
- With those checks actually running, fix the real issues they surface:
  - clippy: useless_conversion in chunked_write.rs, byte_char_slices in
    global_heap.rs/object_header.rs.
  - cargo fmt: apply formatting across the workspace (whitespace only).
  - no_std (thumbv7em-none-eabihf) build errors in clawhdf5-format:
    core::sync::atomic::AtomicU64 doesn't exist on that target (no
    native 64-bit atomics) — switch profiling.rs's counters to
    portable-atomic, which falls back to a CAS-based emulation there
    and is a no-op wrapper elsewhere. Add missing alloc imports for
    Box (filters.rs), Vec (filters_szip.rs), and format! (dict_encoding.rs)
    on no_std paths. Replace f64::powi (std/libm-only) with a small
    local exponentiation-by-squaring helper in the scale-offset filter.

crates/clawhdf5-bench/benches/h5bench_meta.rs

@@ -41,11 +41,7 @@ fn bench_metadata_attrs_write(c: &mut Criterion) {
             let path = tmp.path().join("attrs_libhdf5.h5");
             b.iter(|| {
                 let file = hdf5::File::create(&path).unwrap();
-                let ds = file
-                    .new_dataset::<f64>()
-                    .shape([3])
-                    .create("data")
-                    .unwrap();
+                let ds = file.new_dataset::<f64>().shape([3]).create("data").unwrap();
                 ds.write(&[1.0f64, 2.0, 3.0]).unwrap();
                 for i in 0..k {
                     ds.new_attr::<i64>()
@@ -258,11 +254,7 @@ fn bench_metadata_open_from_disk(c: &mut Criterion) {
         let libhdf5_path = tmp.path().join("open_libhdf5.h5");
         {
             let file = hdf5::File::create(&libhdf5_path).unwrap();
-            let ds = file
-                .new_dataset::<f64>()
-                .shape([3])
-                .create("data")
-                .unwrap();
+            let ds = file.new_dataset::<f64>().shape([3]).create("data").unwrap();
             ds.write(&[1.0f64, 2.0, 3.0]).unwrap();
             ds.new_attr::<i64>()
                 .create("label")
@@ -307,13 +299,17 @@ fn bench_metadata_parse_in_memory(c: &mut Criterion) {
         fb.finish().unwrap()
     };
 
-    group.bench_with_input(BenchmarkId::new("clawhdf5", "in_memory"), &bytes, |b, raw| {
-        b.iter(|| {
-            let file = File::from_bytes(raw.clone()).unwrap();
-            let ds = file.dataset("data").unwrap();
-            ds.attrs().unwrap()
-        });
-    });
+    group.bench_with_input(
+        BenchmarkId::new("clawhdf5", "in_memory"),
+        &bytes,
+        |b, raw| {
+            b.iter(|| {
+                let file = File::from_bytes(raw.clone()).unwrap();
+                let ds = file.dataset("data").unwrap();
+                ds.attrs().unwrap()
+            });
+        },
+    );
 
     group.finish();
 }

crates/clawhdf5-bench/benches/h5bench_read.rs

@@ -74,11 +74,7 @@ fn bench_read_sequential(c: &mut Criterion) {
             let data: Vec<f32> = (0..nn).map(|i| i as f32 * 0.001).collect();
             {
                 let lf = hdf5::File::create(&path).unwrap();
-                let lds = lf
-                    .new_dataset::<f32>()
-                    .shape([nn])
-                    .create("data")
-                    .unwrap();
+                let lds = lf.new_dataset::<f32>().shape([nn]).create("data").unwrap();
                 lds.write(data.as_slice()).unwrap();
             }
             b.iter(|| {
@@ -235,19 +231,23 @@ fn bench_read_zerocopy_mmap(c: &mut Criterion) {
 
         group.throughput(Throughput::Bytes((n * size_of::<f64>()) as u64));
 
-        group.bench_with_input(BenchmarkId::new("clawhdf5_mmap_zerocopy", n), &path, |b, p| {
-            b.iter(|| {
-                let file = MmapFile::open(p).unwrap();
-                let ds = file.dataset("data").unwrap();
-                let slice = ds.read_f64_zerocopy().unwrap();
-                // Sum every element to force the mapped pages to actually be
-                // faulted in — returning just `.len()` would measure nothing
-                // but the mmap() syscall, repeating the exact "too-fast-to-
-                // be-real" mistake this benchmark exists to fix.
-                let sum: f64 = slice.map(|s| s.iter().sum()).unwrap_or(0.0);
-                criterion::black_box(sum)
-            });
-        });
+        group.bench_with_input(
+            BenchmarkId::new("clawhdf5_mmap_zerocopy", n),
+            &path,
+            |b, p| {
+                b.iter(|| {
+                    let file = MmapFile::open(p).unwrap();
+                    let ds = file.dataset("data").unwrap();
+                    let slice = ds.read_f64_zerocopy().unwrap();
+                    // Sum every element to force the mapped pages to actually be
+                    // faulted in — returning just `.len()` would measure nothing
+                    // but the mmap() syscall, repeating the exact "too-fast-to-
+                    // be-real" mistake this benchmark exists to fix.
+                    let sum: f64 = slice.map(|s| s.iter().sum()).unwrap_or(0.0);
+                    criterion::black_box(sum)
+                });
+            },
+        );
 
         group.bench_with_input(BenchmarkId::new("clawhdf5_copy", n), &path, |b, p| {
             b.iter(|| {

crates/clawhdf5-bench/benches/h5bench_write.rs

@@ -63,11 +63,8 @@ fn bench_write_2d_chunked(c: &mut Criterion) {
     let mut group = c.benchmark_group("write_2d_chunked");
 
     // (rows, cols, chunk_rows, chunk_cols)
-    let configs: &[(usize, usize, u64, u64)] = &[
-        (32, 32, 8, 32),
-        (128, 128, 32, 128),
-        (512, 512, 64, 512),
-    ];
+    let configs: &[(usize, usize, u64, u64)] =
+        &[(32, 32, 8, 32), (128, 128, 32, 128), (512, 512, 64, 512)];
 
     for &(rows, cols, cr, cc) in configs {
         let n = rows * cols;
@@ -120,11 +117,8 @@ fn bench_write_2d_chunked(c: &mut Criterion) {
 fn bench_write_2d_chunked_zstd(c: &mut Criterion) {
     let mut group = c.benchmark_group("write_2d_chunked_zstd");
 
-    let configs: &[(usize, usize, u64, u64)] = &[
-        (32, 32, 8, 32),
-        (128, 128, 32, 128),
-        (512, 512, 64, 512),
-    ];
+    let configs: &[(usize, usize, u64, u64)] =
+        &[(32, 32, 8, 32), (128, 128, 32, 128), (512, 512, 64, 512)];
 
     for &(rows, cols, cr, cc) in configs {
         let n = rows * cols;
@@ -132,19 +126,23 @@ fn bench_write_2d_chunked_zstd(c: &mut Criterion) {
         let label = format!("{rows}x{cols}");
         group.throughput(Throughput::Bytes((n * size_of::<f32>()) as u64));
 
-        group.bench_with_input(BenchmarkId::new("clawhdf5/zstd-3", &label), &data, |b, d| {
-            let tmp = TempDir::new().unwrap();
-            let path = tmp.path().join("write_2d_chunked_zstd.h5");
-            b.iter(|| {
-                let mut fb = FileBuilder::new();
-                fb.create_dataset("matrix")
-                    .with_f32_data(d)
-                    .with_shape(&[rows as u64, cols as u64])
-                    .with_chunks(&[cr, cc])
-                    .with_zstd(3);
-                fb.write(&path).unwrap();
-            });
-        });
+        group.bench_with_input(
+            BenchmarkId::new("clawhdf5/zstd-3", &label),
+            &data,
+            |b, d| {
+                let tmp = TempDir::new().unwrap();
+                let path = tmp.path().join("write_2d_chunked_zstd.h5");
+                b.iter(|| {
+                    let mut fb = FileBuilder::new();
+                    fb.create_dataset("matrix")
+                        .with_f32_data(d)
+                        .with_shape(&[rows as u64, cols as u64])
+                        .with_chunks(&[cr, cc])
+                        .with_zstd(3);
+                    fb.write(&path).unwrap();
+                });
+            },
+        );
 
         group.bench_with_input(
             BenchmarkId::new("clawhdf5/deflate-6", &label),
@@ -178,11 +176,8 @@ fn bench_write_2d_chunked_zstd(c: &mut Criterion) {
 fn bench_write_2d_chunked_pcodec(c: &mut Criterion) {
     let mut group = c.benchmark_group("write_2d_chunked_pcodec");
 
-    let configs: &[(usize, usize, u64, u64)] = &[
-        (32, 32, 8, 32),
-        (128, 128, 32, 128),
-        (512, 512, 64, 512),
-    ];
+    let configs: &[(usize, usize, u64, u64)] =
+        &[(32, 32, 8, 32), (128, 128, 32, 128), (512, 512, 64, 512)];
 
     for &(rows, cols, cr, cc) in configs {
         let n = rows * cols;