[libc++][format] Improves escaping.

The change increments the size of the lookup table considerably. The table
has an "upper boundary" check. The removal of the code units with the
property Grapheme_Extend=Yes removes the range E0100..E01EF. This breaks
the trailing large continues section in two parts. This will be improved
in a followup patch.

Implements:
- P2713R1 Escaping improvements in std::format
- LWG3965 Incorrect example in [format.string.escaped] p3 for formatting of combining characters

Before
-----------------------------------------------------------------------
Benchmark                             Time             CPU   Iterations
-----------------------------------------------------------------------
BM_ascii_escaped<char>            95696 ns        95459 ns         7341
BM_unicode_escaped<char>          89311 ns        89088 ns         7835
BM_cyrillic_escaped<char>         58633 ns        58494 ns        11964
BM_japanese_escaped<char>         44500 ns        44382 ns        15780
BM_emoji_escaped<char>            99156 ns        98911 ns         7075
BM_ascii_escaped<wchar_t>         92245 ns        92017 ns         7592
BM_unicode_escaped<wchar_t>       80970 ns        80747 ns         8651
BM_cyrillic_escaped<wchar_t>      51253 ns        51112 ns        13729
BM_japanese_escaped<wchar_t>      37252 ns        37156 ns        18758
BM_emoji_escaped<wchar_t>         96226 ns        95961 ns         7270

After
-----------------------------------------------------------------------
Benchmark                             Time             CPU   Iterations
-----------------------------------------------------------------------
BM_ascii_escaped<char>           110704 ns       110696 ns         6206
BM_unicode_escaped<char>         101371 ns       101374 ns         6862
BM_cyrillic_escaped<char>         63329 ns        63327 ns        11013
BM_japanese_escaped<char>         41223 ns        41225 ns        16938
BM_emoji_escaped<char>           111022 ns       111021 ns         6304
BM_ascii_escaped<wchar_t>        112441 ns       112443 ns         6231
BM_unicode_escaped<wchar_t>      102776 ns       102779 ns         6813
BM_cyrillic_escaped<wchar_t>      58977 ns        58975 ns        11868
BM_japanese_escaped<wchar_t>      36885 ns        36886 ns        18975
BM_emoji_escaped<wchar_t>        115885 ns       115881 ns         6051

Author: mordante

libcxx/docs/ReleaseNotes/19.rst

@@ -50,6 +50,7 @@ Implemented Papers
 - P1659R3 - ``std::ranges::starts_with`` and ``std::ranges::ends_with``
 - P3029R1 - Better ``mdspan``'s CTAD
 - P2387R3 - Pipe support for user-defined range adaptors
+- P2713R1 - Escaping improvements in ``std::format``
 
 Improvements and New Features
 -----------------------------

libcxx/docs/Status/Cxx23Papers.csv

@@ -108,7 +108,7 @@
 "`P2164R9 <https://wg21.link/P2164R9>`__","LWG", "``views::enumerate``","February 2023","","","|ranges|"
 "`P2711R1 <https://wg21.link/P2711R1>`__","LWG", "Making multi-param constructors of ``views`` ``explicit``","February 2023","|In Progress| [#note-P2711R1]_","","|ranges|"
 "`P2609R3 <https://wg21.link/P2609R3>`__","LWG", "Relaxing Ranges Just A Smidge","February 2023","","","|ranges|"
-"`P2713R1 <https://wg21.link/P2713R1>`__","LWG", "Escaping improvements in ``std::format``","February 2023","","","|format|"
+"`P2713R1 <https://wg21.link/P2713R1>`__","LWG", "Escaping improvements in ``std::format``","February 2023","|Complete|","19.0","|format|"
 "`P2675R1 <https://wg21.link/P2675R1>`__","LWG", "``format``'s width estimation is too approximate and not forward compatible","February 2023","|Complete|","17.0","|format|"
 "`P2572R1 <https://wg21.link/P2572R1>`__","LWG", "``std::format`` fill character allowances","February 2023","|Complete|","17.0","|format|"
 "`P2693R1 <https://wg21.link/P2693R1>`__","LWG", "Formatting ``thread::id`` and ``stacktrace``","February 2023","|Partial| [#note-P2693R1]_","","|format|"

libcxx/docs/Status/Cxx2cIssues.csv

@@ -32,7 +32,7 @@
 "`3951 <https://wg21.link/LWG3951>`__","[expected.object.swap]: Using ``value()`` instead of ``has_value()``","Kona November 2023","","",""
 "`3953 <https://wg21.link/LWG3953>`__","``iter_move`` for ``common_iterator`` and ``counted_iterator`` should return ``decltype(auto)``","Kona November 2023","","","|ranges|"
 "`3957 <https://wg21.link/LWG3957>`__","[container.alloc.reqmts] The value category of v should be claimed","Kona November 2023","","",""
-"`3965 <https://wg21.link/LWG3965>`__","Incorrect example in [format.string.escaped] p3 for formatting of combining characters","Kona November 2023","","","|format|"
+"`3965 <https://wg21.link/LWG3965>`__","Incorrect example in [format.string.escaped] p3 for formatting of combining characters","Kona November 2023","|Complete|","19.0","|format|"
 "`3970 <https://wg21.link/LWG3970>`__","[mdspan.syn] Missing definition of ``full_extent_t`` and ``full_extent``","Kona November 2023","","",""
 "`3973 <https://wg21.link/LWG3973>`__","Monadic operations should be ADL-proof","Kona November 2023","","",""
 "`3974 <https://wg21.link/LWG3974>`__","``mdspan::operator[]`` should not copy ``OtherIndexTypes``","Kona November 2023","","",""

libcxx/docs/Status/FormatIssues.csv

@@ -10,7 +10,7 @@ Number,Name,Standard,Assignee,Status,First released version
 "`P2508R1 <https://wg21.link/P2508R1>`__","Exposing ``std::basic-format-string``","C++23","Mark de Wever","|Complete|",15.0
 "`P2585R0 <https://wg21.link/P2585R0>`__","Improving default container formatting","C++23","Mark de Wever","|Complete|",17.0
 "`P2539R4 <https://wg21.link/P2539R4>`__","Should the output of ``std::print`` to a terminal be synchronized with the underlying stream?","C++23","Mark de Wever","|Complete|","18.0"
-"`P2713R1 <https://wg21.link/P2713R1>`__","Escaping improvements in ``std::format``","C++23","Mark de Wever",""
+"`P2713R1 <https://wg21.link/P2713R1>`__","Escaping improvements in ``std::format``","C++23","Mark de Wever","|Complete|",19.0
 "`P2675R1 <https://wg21.link/P2675R1>`__","``format``'s width estimation is too approximate and not forward compatible","C++23","Mark de Wever","|Complete|",17.0
 "`P2572R1 <https://wg21.link/P2572R1>`__","``std::format`` fill character allowances","C++23","Mark de Wever","|Complete|",17.0
 "`P2693R1 <https://wg21.link/P2693R1>`__","Formatting ``thread::id`` and ``stacktrace``","C++23","Mark de Wever","|In Progress|"