Fix Home, End, and repeated page navigation

[BuildScript (buildscript-dev)]

Fixes #118.

Summary

• handle standard ncurses KEY_HOME and KEY_END inputs in addition to the existing Ctrl+Home/Ctrl+End sequences
• allow Page Up and Page Down to continue navigating while the keys repeat instead of stopping after ten pages
• document the navigation keys in the built-in help view

Validation

• git diff --check
• CMake configuration attempted; this environment does not have the required ncurses development library (libncursesw.so.6), so a full local build could not be completed

[BuildScript (buildscript-dev)]

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