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/pages/pages_surfaces.go

@@ -35,7 +35,6 @@ func (e *Engine) SeedSurfaces() {
 	}
 	log.Printf("[pages] Seeded %d core surfaces into registry", len(e.surfaces))
 
-	// v0.31.0: Clean up old "editor" core surface row.
 	// Editor is now an installable package — the old seed row would show a
 	// broken nav link until the package .pkg is uploaded via admin UI.
 	if sr, err := e.stores.Packages.Get(ctx, "editor"); err == nil && sr != nil && sr.Source == "extension" {