style: remove every em-dash and en-dash

Eighteen occurrences across fourteen files. Each sentence was repunctuated to
suit what the dash was doing rather than swapped for a hyphen, which produces
comma splices. The minus sign in folio-web's ledger is a minus sign and stays.

Claude-Session: https://claude.ai/code/session_01A5KmftdEJ49A9z5mF5ESrX

CLAUDE.md

@@ -17,7 +17,7 @@
 
 ## PR Rules
 
-  - Simple PR title, few-line description. Never write a wall of text — nobody reads it.
+  - Simple PR title, few-line description. Never write a wall of text. Nobody reads it.
   - Everything lowercase in PR titles, descriptions, and comments.
 
 ### PR Description Rules