milestone 18: collapse duplicated infrastructure into shared listener core, crud list helper, resource shells, transport race, name and line helpers, ui modules

src/cache/dns_cache.zig

@@ -45,6 +45,10 @@ pub const max_key_len = types.max_name_len + 1 + 2 + 2 + 1 + 1 + max_ecs_len;
 ///
 /// The length bounds are assertions, not errors: both values reach here from
 /// the packet parser, which has already rejected anything longer.
+///
+/// The lowercase-and-strip-the-dot below is deliberately not
+/// `dns.name.normalizeText`: that one validates, and this input is already
+/// asserted valid, so a key build must never fail.
 pub fn buildKey(
     buf: *[max_key_len]u8,
     qname: []const u8,