Incremental package builds and releases on v* tags (0.8.0)

- build-packages.sh rebuilds a package only when its srcpkgs/ directory
  changed, its binary package is missing, or a dry-run install finds a
  shared library Void no longer provides; DASOS_REBUILD=1 rebuilds all.
  An unchanged `make packages` takes 20 s instead of 17 min on the CI host
- ci/release.sh publishes both ISOs and SHA256SUMS as a Gitea release
  when the workflow runs for a v* tag matching VERSION
- README and TODO updated

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -1,7 +1,7 @@
 ## Das OS
 ### _A light, friendly Void Linux–based desktop with Xfce and a Ukrainian touch, plus a console server edition_
 
-[![Void Linux](https://img.shields.io/badge/Void_Linux-x86__64_glibc-green)](https://voidlinux.org) [![Xfce](https://img.shields.io/badge/Xfce-4.20-orange)](https://xfce.org) [![runit](https://img.shields.io/badge/init-runit-blue)](https://docs.voidlinux.org/config/services/) [![Go](https://img.shields.io/badge/Go-1.24+-blue)](https://go.dev) [![Docker](https://img.shields.io/badge/Docker-29-blue)](https://www.docker.com) [![Version](https://img.shields.io/badge/version-0.7.0-lightgrey)](#)
+[![Void Linux](https://img.shields.io/badge/Void_Linux-x86__64_glibc-green)](https://voidlinux.org) [![Xfce](https://img.shields.io/badge/Xfce-4.20-orange)](https://xfce.org) [![runit](https://img.shields.io/badge/init-runit-blue)](https://docs.voidlinux.org/config/services/) [![Go](https://img.shields.io/badge/Go-1.24+-blue)](https://go.dev) [![Docker](https://img.shields.io/badge/Docker-29-blue)](https://www.docker.com) [![Version](https://img.shields.io/badge/version-0.8.0-lightgrey)](#)
 
 🇺🇦 [Українська версія](README_ua.md)
 
@@ -180,6 +180,7 @@ Void Linux is fast, simple and independent: runit instead of systemd, and its ow
 - `srcpkgs/das-server` is the server metapackage with the nftables, fail2ban, sshd and Docker defaults. `srcpkgs/das-helpers` contains `dsv`, `duser`, `dfw`, `dsys`, `dprofile` and the profiles.
 - `srcpkgs/calamares`, `srcpkgs/adw-gtk3` and `srcpkgs/font-jetbrains-mono` package upstream releases that Void does not have.
 - `make packages` lays the templates over a shallow clone of void-packages and builds them with `xbps-src` into `out/hostdir/binpkgs`. The ISO build installs them from there.
+- A package is rebuilt only when its directory in `srcpkgs/` changed, its binary package is missing, or Void no longer provides a shared library it links to (checked with a dry-run install). `DASOS_REBUILD=1 make packages` rebuilds everything.
 
 #### Containerised build<a id='Build' />
 **_The whole build runs in a Docker container, so only Docker and QEMU are needed on the host._**
@@ -193,7 +194,7 @@ Void Linux is fast, simple and independent: runit instead of systemd, and its ow
 - The runner is a WSL2 distro on a Windows machine: Ubuntu 24.04 with Docker Engine and `gitea-runner` as a systemd service. A scheduled task starts it when Windows boots, no login needed.
 - `ci/runner/setup.sh` installs Docker, the runner and its `config.yaml`; `setup.sh register <token>` registers it, `autostart.ps1` creates the scheduled task.
 - `DASOS_OUT` moves `out/` out of the checkout, so void-packages, the bootstrapped masterdir and the download cache survive between builds.
-- The ISOs stay on the CI host in `/var/lib/dasos-ci/out/iso` and are not published yet.
+- A `v*` tag that matches `VERSION` also publishes both ISOs and `SHA256SUMS` as a release (`ci/release.sh`, with the job's own token): `git tag v0.8.0 && git push origin v0.8.0`. Other builds keep the ISOs on the CI host in `/var/lib/dasos-ci/out/iso`.
 
 ### 🚀 Building the application
 Requirements: Linux with Docker (the user must be in the `docker` group), QEMU and OVMF for testing, and Go 1.24+ with the GTK 3 development files for `make test`. About 10 GB of free disk space.
@@ -207,6 +208,6 @@ make clean               # remove build output, keep the download cache
 ```
 The ISOs appear in `out/iso/dasos-<version>-x86_64.iso` and `out/iso/dasos-server-<version>-x86_64.iso`. Write them to a USB stick with `dd` or Ventoy.
 
-**Note:** Das OS is an early version (0.7.0). Packages and ISOs are built in CI; signed repository hosting is planned for an upcoming stage. Until the repository is hosted, an installed system gets updates from Void only. Das OS is based on Void Linux but is not affiliated with it.
+**Note:** Das OS is an early version (0.8.0). Packages and ISOs are built in CI; signed repository hosting is planned for an upcoming stage. Until the repository is hosted, an installed system gets updates from Void only. Das OS is based on Void Linux but is not affiliated with it.
 
 ###### _Made by -=:dAs:=-_