gh-145896: Fix typos and stale docstrings in Lib/traceback.py

[devdanzin]

This PR fixes some typos and stale docstrings, as described by Claude Code:

• Fix stale extract_tb() docstring: add end_lineno, colno, and end_colno to the listed FrameSummary attributes (available since 3.11)
• Fix stale extract_stack() docstring: replace outdated "quadruple (filename, line number, function name, text)" with "FrameSummary object" (stale since 3.5)
• Fix broken grammar in FrameSummary class docstring: "for the of code" → "for the code"
• Fix inaccurate _display_width() docstring: "extra amount of width" → "amount of width" (the function returns total display width, not a delta)
• Fix copy-paste typo in TracebackException.__init__ comment: "exc_traceback, exc_value, exc_traceback" → "exc_type, exc_value, exc_traceback"

• Issue: Typos and stale docstrings in Lib/traceback.py #145896

[picnixz]

Can you also check that any public doc matches this one (or is as long as the internal one) please?

[devdanzin]

Not sure what you mean by "is as long as the internal one", but I've corrected the same staleness and some typos in the traceback public documentation.

[picnixz]

By "as long as", I meant that we were precise enough in the public docs