Dependency issue

**Describe the bug**
Hello, I just recently installed exoplanet and am working through the "Fitting TESS data" Case study. I tried to run the transit model in Pymc3 code and have run into several issues regarding dependencies.

First, I got the error saying that no module labeled "pymc3" exists.

Then I got the error that no module labeled "aesara-theano-fallback" exists.

Then I got another error saying that No modules labeled "aesara, theano-pymc, or theano" are installed.

**To Reproduce**
I just used the same snippet of code from the case study of Fitting TESS light curves in the section labeled "The transit model in PyMC3"

**Your setup (please complete the following information):**
- Version of exoplanet: 0.6.0
- Operating system: Windows 11 but running code on a WSL which is Ubuntu 24.02.3
- Python version & installation method (pip, conda, etc.): Python version 3.14.3 and using pip

Start with the “Fitting TESS light curves” case study, specifically the “The transit model in PyMC3” snippet, and reproduce the reported errors in the stated Python 3.14.3 and exoplanet 0.6.0 environment. Check how the documented dependencies relate to the missing pymc3, aesara-theano-fallback, aesara, theano-pymc, and theano modules. Done means the case-study transit model has a documented, working dependency path.

Written by the indexing model from the issue text.