[Bug]: Table sorting broken for numerical cell values

Nobody has claimed this yet.

**Describe the bug**

Sorting table columns doesn't work as expected for numerical values: given sorting is alphabetical, values like 1, 2, 10, 20 are sorted 1, 10, 2, 20 with the provided javascript. Sorting should be smart enough to account for this, including decimals and negative numbers and ignoring units if the same for all cells, both appended (e.g. GiB) and prepended (currency).

Probably should sort first any figures, then alphabetically, ascending. I wonder though if for numbers descending is a better default (it can be for instance in web analytics).

Split from https://github.com/canonical/vanilla-framework/pull/5736

**To Reproduce**

I edited the _table-sortable .html file, replacing the table code with this for better testing:

```html

Status
Cores
RAM
Disks




Ready
1
1.1 GiB
2


Failed
10
1 GiB
Pending


Pending
8
3.9 GiB
3


Ready
8
10.9 GiB
Unknown

```

Example is available in /docs/examples/patterns/tables/table-sortable

**Expected behavior**

Numeric values are sorted correctly when clicking on the column header.

**Screenshots**

Start with /docs/examples/patterns/tables/table-sortable and inspect the provided JavaScript and its current sorting behavior using the reproduction table. Clarify the ordering for mixed numeric and text values, decimals, negative numbers, and shared prepended or appended units. Done means clicking a column header sorts numeric values numerically while preserving the expected alphabetical fallback.

Written by the indexing model from the issue text.