Implement icdf for Truncated distributions

[prisharai]

Description

Registers _icdf for TruncatedRV so pm.icdf works with pm.Truncated whenever the base distribution has an icdf.

Follows the suggestions in #8354 (comment): uses _create_logcdf_exprs (which handles the -1 for discrete), rescales the quantile onto [cdf(lower), cdf(upper)] in logspace, and passes it to the base icdf. This is the same expression rv_op uses for inverse-CDF sampling. q = 1 maps exactly to cdf(upper) so roundoff can't push it past the boundary. Bases without an icdf still raise NotImplementedError.

Related Issue

• Closes #
• Related to Add icdf functions for distributions #6612

Checklist

• Checked that the pre-commit linting/style checks pass
• Included tests that prove the fix is effective or that the new feature works
• Added necessary documentation (docstrings and/or example notebooks)
• If you are a pro: each commit corresponds to a relevant logical change

Type of change

• New feature / enhancement
• Bug fix
• Documentation
• Maintenance
• Other (please specify):

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Documentation build overview

📚 pymc | 🛠️ Build #33659334 | 📁 Comparing b7797b8 against latest (91157fd)

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2 files changed

± glossary.html
± _modules/pymc/distributions/truncated.html