Changes required for ArviZ 1.0

[cdc-mitzimorris]

ArviZ 1.0 uses an xarray.DataTree structure to organizes the MCMC output, replacing the InferenceData object.

The xarray.DataTree can handle hierarchical structures, and interprets the / as a path separator. This doesn't play nicely with NumPyro's use of the / as the default separator for nested scope. To avoid conflict, we should use :: for scope.

The tutorial "Building Multisignal Models" uses Arviz and to diagnose and visualize the sample and has been updated accordingly.

Note: this PR will fail until #737 goes in.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.31%. Comparing base (079f9ca) to head (d6c6494).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #754      +/-   ##
==========================================
+ Coverage   97.87%   98.31%   +0.44%     
==========================================
  Files          48       48              
  Lines        1550     1485      -65     
==========================================
- Hits         1517     1460      -57     
+ Misses         33       25       -8     

Flag	Coverage Δ
unittests	98.31% <100.00%> (+0.44%)	⬆️

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[dylanhmorris]

Thanks @cdc-mitzimorris! Looks like there are a couple remaining references to the old scope formating that are causing the website build to fail

https://github.com/CDCgov/PyRenew/actions/runs/23357225847/job/67951096307?pr=754

---> 14     f"Rt baseline samples: {prior_samples['latent_infections/rt_baseline'].shape}"

[github-actions]

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