vanderbilt: store raw_data with gzip in the four files ClamAV flags

Stores `tracks/track_0/data/raw_data` with shuffle + gzip (level 4) instead of Blosc in the four `data/Fundamental/` files that the Hub's ClamAV scan marks unsafe (`Win.Exploit.CVE_2016_4332_1-6028013-0`):

- `126987_3_Focused_Uncoded_TX.hdf5`
- `559277_2_Focused_Uncoded_TX.hdf5`
- `729304_2_Focused_Uncoded_TX.hdf5`
- `829312_1_Focused_Uncoded_TX.hdf5`

The matching bytes sit inside Blosc-compressed `raw_data` chunks, not in the HDF5 object headers the CVE is about, so this is a false positive (reported to ClamAV). Re-encoding with Blosc at another level or shuffle mode only clears some files (#82). gzip changes the chunk bytes completely and is the same fix as #83 for UBC `session_01_f0374.hdf5`.

Files changed: 4. Only the compression filter of `raw_data` changed. Its values, dtype, shape, chunk shape and fill value, every other dataset (still Blosc) and every attribute are untouched. The Sept 26 subject-ID fix (#74) is kept, since the files were rewritten from current `main`.

Checks, each file against current `main` (source SHA-256 matched the Hub):

- All 24 datasets compared byte-for-byte after decompression, including all 32 `raw_data` frames; all 53 attributes compared by name, order, dtype and value; dtype, shape, maxshape, chunks and fill value compared for every dataset. 0 differences.
- zea 0.1.7: `File.validate()` succeeds, and `scan`, `metadata`, `load_parameters()` and a full `raw_data` read run with no warnings (same as the originals).
- ClamAV 1.4.3, daily 28140 (`--allmatch --max-filesize=1900M --max-scansize=2000M --max-scantime=0 --alert-exceeds-max=yes`): all four originals are flagged, all four replacements are clean.

| File | Original bytes | Replacement bytes |
|---|---:|---:|
| 126987_3_Focused_Uncoded_TX.hdf5 | 1171259392 | 1163677695 |
| 559277_2_Focused_Uncoded_TX.hdf5 | 1043398656 | 1019994734 |
| 729304_2_Focused_Uncoded_TX.hdf5 | 1061224448 | 1026541803 |
| 829312_1_Focused_Uncoded_TX.hdf5 | 1111031808 | 1080546952 |

Diff (`h5_diff` against `main`: file hashes differ, no structure, dtype, shape, attribute or metadata change):

```
vanderbilt/data/Fundamental/126987_3_Focused_Uncoded_TX.hdf5: differs (main)
vanderbilt/data/Fundamental/559277_2_Focused_Uncoded_TX.hdf5: differs (main)
vanderbilt/data/Fundamental/729304_2_Focused_Uncoded_TX.hdf5: differs (main)
vanderbilt/data/Fundamental/829312_1_Focused_Uncoded_TX.hdf5: differs (main)
```

Storage of `raw_data`, before -> after:

```
~ tracks/track_0/data/raw_data: filters [blosc (zstd, clevel 7, bitshuffle)] -> [shuffle, gzip 4]
```

Hugging Face's own scan of the new files should be checked before merging.

<details><summary>Replacement SHA-256 hashes</summary>

- `vanderbilt/data/Fundamental/126987_3_Focused_Uncoded_TX.hdf5`: `2c205f460bfd00eee82e7ebc13c84e44208658104548434c58f59a3822fa171c`
- `vanderbilt/data/Fundamental/559277_2_Focused_Uncoded_TX.hdf5`: `09026325a76ec701c1f25ac17e267ec4850c6a1dfb090a6525cefbac3a4871a4`
- `vanderbilt/data/Fundamental/729304_2_Focused_Uncoded_TX.hdf5`: `6c3c4f8717107a98e64d76f1dfae29f93cb11aaa3db0f97d1b9986581cb00773`
- `vanderbilt/data/Fundamental/829312_1_Focused_Uncoded_TX.hdf5`: `a0c549afe4ad4f61a9d96ea50d5dcc57de3f149898f593a8daf4bc697795267e`

</details>

🤖 Generated with [Claude Code](https://claude.com/claude-code)

vanderbilt/data/Fundamental/126987_3_Focused_Uncoded_TX.hdf5

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:4705fc748b4a2b4654c38c06aa062fd8ba083a3ec91a31569b595ac0a32c7f9b
-size 1171259392
+oid sha256:2c205f460bfd00eee82e7ebc13c84e44208658104548434c58f59a3822fa171c
+size 1163677695

vanderbilt/data/Fundamental/559277_2_Focused_Uncoded_TX.hdf5

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:7ca38fca377f29a655b99f41459c6f89befe93b2aad21b6f4a9186acf761da3b
-size 1043398656
+oid sha256:09026325a76ec701c1f25ac17e267ec4850c6a1dfb090a6525cefbac3a4871a4
+size 1019994734

vanderbilt/data/Fundamental/729304_2_Focused_Uncoded_TX.hdf5

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:3391cbc8f0f52342a0907240ed16d28b2651eacf37727ad2fc74c532781345cd
-size 1061224448
+oid sha256:6c3c4f8717107a98e64d76f1dfae29f93cb11aaa3db0f97d1b9986581cb00773
+size 1026541803

vanderbilt/data/Fundamental/829312_1_Focused_Uncoded_TX.hdf5

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:212450a9fe620a659f167dbfe543c8d7a26ec5c8c9139238ffae50e341540db2
-size 1111031808
+oid sha256:a0c549afe4ad4f61a9d96ea50d5dcc57de3f149898f593a8daf4bc697795267e
+size 1080546952