RzShell: refactor string, regex and byte search

[Rot127]

Your checklist for this pull request

• I've read the guidelines for contributing to this repository
• I made sure to follow the project's coding style
• I've documented or updated the documentation of every function and struct this PR changes. If not so I've explained why.
• I've added tests that prove my fix is effective or that my feature works (if possible)
• I've updated the rizin book with the relevant information (if needed)

Supersedes #4762

Detailed description

Changes made

• Moves all legacy search commands to RzShell (only commands, inside they still do their string parsing on arguments).
• Refactor string and byte search
• Move to RzShell
• Moves: / to /z.
• Add support for Unicode and EBCDIC string search.
• Add support for (Unicode) regex string search.
• Add support for byte string regex search /xr.
• Add more details to the search help messages.
• Offsets of the search hits align with the actual encoding. Not with the UTF-8 encoding.
• Dispatches memory chunks for search into threads.
• Changes to ps
  • Adds extra arguments to specify encoding (also EBCDIC).
  • Add additional delimiter argument (stop at first non-printable).
  • Document it more.
  • Add psu alias for ps utf8
• Changes to Settings
  • Remove str.search.max_uni_blocks - Effectively a metric the user should not know about; adds too much complexity.
  • str.search.max_threads -> search.max_threads - This is a general setting for the search now.
  • str.search.raw_alignment -> search.str.raw_alignment - Unify settings (only used for RzBin search.).
  • str.search.encoding -> str.encoding - Valid for all string interpretations.
  • str.search.min_length -> search.str.min_length - Unify settings.
  • str.search.buffer_size -> search.str.max_length - Unify settings.
  • str.search.max_region_size -> search.str.max_region_size - Unify settings.
  • str.search.check_ascii_freq -> search.str.check_ascii_freq - Unify settings.
• Removed commands
  • /! - Because the command modifiers are not properly handled in RzShell yet and the advantage of this one is dubious (IMHO).
  • /f - Modifier and obsolete, because search is dispatched into threads.
  • /b - Modifier and obsolete, because search is dispatched into threads.
  • /+ - Because no idea what it does. Seems not particular useful.
  • /e - Replaced with regex search in bytes and string search.
  • /w - All Unicode is searched now properly with /z.
• Make some changes to the string escaping, so it works reliably with Unicode characters.
  • The RzStrEscOptions were inconsistently used.
    E.g. show_asciidot (replace non-printable ascii with dot) was ignored for \n, \t etc.
  • Defined Unicode code points are escaped now with \U00hhhhhh. All other non-printable bytes are escaped with \xhh. There are still some exceptions (when legacy escape functions are used) but most places are ok now.
• General
  • Fix inconsistencies in Unicode decoders/encoders and checkers. They now either return 0 on an invalid decode or the number of bytes the code point requires.
  • Add many unit tests for Unicode related logic.
  • Update Unicode tables to Version 16.
  • Add helper to check code points.
  • Escaped strings now escape valid Unicode code points to /Uhhhhhh (if not requested otherwise by the user) and invalid code points to /xhh.
  • Add helper functions for hexadecimal strings and bits.

TODO Overview

Open issues

• GCC-12 flag: 6109a0b
• Search hits of strings should contain length in characters/code points and graphemes. cc @kazarmy
• Add option to define search strategy (graph algos, address window sizes etc.).
• Add option to define what are "unprintable character" exceptions (e.g. \t, \n etc.).

Documentation

• Update book about search:
  • API
  • commands
  • examples
  • edge cases (e.g. diacritics, regex search PCRE2)

Test plan

Tests were added

Closing issues

closes #4910

[notxvilka]

LGTM.