docs(adr): Halkyon Days, its apps, names and domains

ADR 0045: the project becomes Halkyon Days; Halkyon is the learning app,
Myrmex the task app, Keyx a voice assistant later. halky.one is the
project's site, halkyon.li and myrmex.li its public instances with
separate registers, signing in by email, password and authenticator
alone. The code takes the prefix halkyone_, the app IDs one.halky.*,
the organisation the name halkyon-days. It amends ADR 0039, whose
halkyon.li was the family's instance alone.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

docs/adr/0039-halkyon-li-at-home.md

@@ -8,6 +8,9 @@
   themselves and their close family"), ADR 0016 (the instance's register), ADR 0020
   (SimpleLogin), ADR 0030, 0033 and 0038 (Train's, Todo's and Meditate's servers beside
   Learn's).
+- **Amended by:** ADR 0045 (12 Nov 2026): halkyon.li becomes Halkyon's public
+  instance, no longer the family's alone; Train and Meditate keep registers of their
+  own.
 - **Supersedes:** ADR 0032 (Jellyfin at home through a tunnel to learn.halkyon.eu's
   server), whose server end is retired with sahaquiel; its open question goes with it.
 - **Followed by:** the Instance console's ADR (to come), through which halkyon.li's