docs: Simplify "More on Lists" section in tutorial

[dagangtj]

This PR simplifies the "More on Lists" section in the tutorial by replacing detailed .. method:: directives with concise descriptions and links to the Library Reference.

Changes

• Replaced 11 detailed .. method:: directive blocks with a simple bullet list
• Each list item contains a method reference (:meth:~list.method``) and a brief description
• Added a note directing readers to the Library Reference for complete documentation

Rationale

As noted in #146487:

• The "More on Lists" subsection was the only place in the tutorial using Sphinx .. method:: directives to provide formal definitions
• These definitions were largely duplicated from the Library Reference
• The list class was the only built-in class described in such detail in the tutorial
• Index entries point to the Library Reference rather than the tutorial

This change brings the list method descriptions in line with how other built-in types (like dict and set) are described in the tutorial—using concise descriptions with links to the full Library Reference documentation.

Verification

• Documentation builds successfully with make html
• No warnings or errors introduced

Fixes: #146487

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📚 Documentation preview 📚: https://cpython-previews--146508.org.readthedocs.build/