[Feature] @names for quickly constructing named labels

[lkdvos]

This is a small convenience feature for making the syntax slightly less heavy, inspired by @syms from the symbolic computing ecosystem.
The main idea is to simply create variables that are bound to a named symbol of the same "name", allowing the following:

using NamedDimsArrays: @names

@names x y z
a = randn(2, 2)
b = randn(2, 2)
a[x, y] * b[y, z]

Obviously the name can be changed , I just wanted to float the idea.

Possible extensions are also to support @names x, y, z instead/additionally.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 71.13%. Comparing base (ad46ea4) to head (a069a66).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #105      +/-   ##
==========================================
+ Coverage   71.00%   71.13%   +0.12%     
==========================================
  Files          16       16              
  Lines         921      925       +4     
==========================================
+ Hits          654      658       +4     
  Misses        267      267              

Flag	Coverage Δ
docs	25.38% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[emstoudenmire]

Lukas and I discussed this today, and while I like it, I suggested the synax:

x, y, z = @names x y z

to make it more explicit to users that new references are being created, and that having the references match the symbol values is a choice (i.e. a, b, c = @names x y z would also be ok).