docs: write prose without dashes or semicolons

Profiles, the wiki, comments, docstrings, command output and schema descriptions carried em-dashes, clause-joining semicolons, unicode arrows, box-drawing banners and check-mark glyphs. Each sentence was rewritten rather than having its character swapped. Hashes, paths, source_ref values and every cited file:line are unchanged, which a comparison of each parsed profile against the previous revision confirms.

validate_pr comments now say PASS and FAIL in words, and source_ref values in a profile's structured blocks render as code. test_prose_style fails if any of these comes back, in tracked files or in the generated site.

scripts/__init__.py

@@ -3,7 +3,7 @@
 These modules are run as scripts (``python scripts/verify.py``), as modules
 (``python -m scripts.scraper.libretro_scraper``), and imported as a package by
 the tests and the type checker. The first form puts this directory on the path
-itself; the other two do not, so importing the package adds it. Without that,
+itself. The other two do not, so importing the package adds it. Without that,
 ``import scripts.common`` fails on the first sibling import it reaches, and
 every absolute import between siblings would have to be rewritten to be
 relative -a change that would break running a script directly.