iso: calamares from [tanin] (AUR rebuild); document the build step

- packages.x86_64: calamares enabled (served from [tanin])
- finish/build-tanin-repo.sh: add calamares to the AUR rebuild list
- BUILD.md + manifest: calamares rebuild step + status

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

iso/BUILD.md

@@ -26,6 +26,19 @@ sudo pacman -S archiso          # to build
   `overrides/packages.x86_64` (currently commented out), or the build fails.
   (Rebuild like eww-git: `paru-bin` via makepkg → `publish-tanin-repo.sh`.)
 
+## First: put calamares (and the other AUR rebuilds) into [tanin]
+`calamares` is AUR-only, so mkarchiso can't pull it from the official repos — it
+must live in `[tanin]`. Heavy Qt build (installs makedepends via sudo):
+```sh
+cd /tmp && rm -rf calamares && git clone https://aur.archlinux.org/calamares.git
+cd calamares && makepkg -sf --noconfirm
+cp ./*.pkg.tar.zst ~/projects/tanin-repo/
+# publish (create a write:package token in Gitea → Settings → Applications):
+TANIN_PKG_TOKEN=<token> ~/projects/taninux/packaging/publish-tanin-repo.sh
+```
+(If the AUR `calamares` lags a Qt bump, try `calamares-git`, or fall back to
+`archinstall` — already in the live base.)
+
 ## Build
 ```sh
 ./bootstrap-profile.sh          # assemble build-profile/ (releng base + overrides)

iso/overrides/packages.x86_64

@@ -19,10 +19,10 @@ snap-pac
 # boot splash
 plymouth
 
-# live installer host (cage). calamares is AUR -> rebuild into [tanin] first,
-# then uncomment (see BUILD.md). archinstall (TUI) is already in the releng base.
+# live installer: cage hosts calamares. calamares is AUR -> served from [tanin]
+# (rebuild via finish-tanin-repo.sh / the calamares one-liner in BUILD.md).
 cage
-#calamares
+calamares
 
 # target bootloader
 efibootmgr