chore: strip pre-fork version comments across 72 files

Removes standalone "// v0.X.X:" comment lines and inline trailing
version annotations. Keeps version references in config field docs
and compatibility notes where they describe requirements.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/sandbox/unicode_scan.go

@@ -1,6 +1,5 @@
 // Package sandbox — unicode_scan.go
 //
-// v0.5.1: Invisible Unicode scanning gate.
 //
 // Defends against GlassWorm (variation selector payloads), Trojan Source
 // (bidi override attacks / CVE-2021-42574), and other invisible Unicode