Make Hermes and Artemis session-less fleet foundation, add STARTUP-BANNER

Per FABRIC-3.md D.7 (birth-by-message-only): the Tripod legs must be alive
session-less before any thumbdrive-attach flow has a running Hermes/Artemis
to message. kernel_main.c's item 4.2/4.6 self-tests previously birthed
both, exercised diagnostics, then explicitly KILLed them before ok> every
boot -- production boot never actually kept either alive. Stripped both
blocks down to birth-only, diagnostics and KILL removed.

Found and fixed a real regression this surfaced, not left broken: Hermes's
CD-INIT (message/channel arena init, and the thing that loads lib.4th into
her own dictionary) was only ever invoked by the self-test just removed --
nothing in hermes/init.4th itself called it. Added an unconditional CD-INIT
call at the end of her own init.4th so a real birth actually initializes
her arena, matching how Artemis's own ART-BOOT-ENTRY already runs
unconditionally at her own capsule load.

Added STARTUP-BANNER (lib.4th): a shared word reading a common
IDENTITY-BANNER buffer, printing "(no identity)" until CERTVERIFY/MINT
exist to populate it from a thumbdrive's PKI fields -- scaffolding only,
per direct instruction. Wired into each Tripod leg's own init.4th
(Hera/Hermes/Artemis); Artemis didn't load lib.4th before, added that too.

Verified live on all three architectures: BIRTH for both, no KILL anywhere
in any log, and an interactive USE round-trip confirmed Hermes is
genuinely reachable post-boot, not just logged as born.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019ZGkimpfyh63EZyRkNbkPD

capsules/lib.4th

@@ -10,3 +10,8 @@ Block 4050
 : CSV-COL  ( n -- ) N. COMMA ;
 : CSV-LAST ( n -- ) N. CRLF ;
 : Q.SHOW ( q -- ) Q.PRINT CR ;
+CREATE IDENTITY-BANNER 128 ALLOT
+VARIABLE IDENTITY-BANNER-LEN  0 IDENTITY-BANNER-LEN !
+: STARTUP-BANNER ( -- ) IDENTITY-BANNER-LEN @ 0= IF
+  ." (no identity)" CR EXIT THEN
+  IDENTITY-BANNER IDENTITY-BANNER-LEN @ TYPE CR ;