lib: banner purge + WHY-only comment sweep (rule 8)

Every // ---- section banner dies (132 -> 0): names carry the WHAT.
Narration deleted (filename restatements, run-with lines, what-the-
next-line-does); every ref/hare cite, task cite, divergence, ABI/
layout contract, and ownership qualifier kept (borrowed-view lines
restored where the sweep over-cut). Comment-only proven: all 442
walk-workdir .s and 32 import-probe .s byte-identical before/after;
libbyteid 56-roster all-ID.

lib/net/net.ww

@@ -1,7 +1,5 @@
-// net — minimal TCP. Sketched against the Linux syscall numbers
-// 41 (socket), 42 (connect), 43 (accept), 49 (bind), 50 (listen).
-// Real applications will want addrinfo + DNS; we leave that to
-// higher layers.
+// net — minimal TCP. Real applications will want addrinfo + DNS; we
+// leave that to higher layers.
 
 package net;