Fail loudly when release uploads do not land

Follow-up to the publishing fix: CI created the v0.2.11 release and logged each
upload, but the assets never arrived, so the job looked successful while the
release was empty. The host root filesystem is full (7.8G, 100%), and Gitea
answered HTTP 500 "Attachments.Save: no space left on device".

- publish_release.sh now checks the HTTP status of every asset upload and prints the
  response body on failure, then verifies the release reports as many assets as were
  sent. Empty releases can no longer pass silently.
- Deleted the empty v0.2.11 release so the "latest" release (v0.2.10) still has all
  five artifacts; the tag itself remains.
- TODO/MEMORY record the host disk blocker with concrete cleanup commands and note
  that v0.2.11 artifacts are built locally in build/ for upload once space exists.

MEMORY.md

@@ -148,7 +148,16 @@ Session memory for durable decisions, state, and gotchas. Keep concise, remove o
   `actions/checkout` writes (`git config --local --get-regexp '^http\..*\.extraheader$'`),
   which carries the runner's basic-auth credentials for the same server. Verified locally by
   adding that extraheader and publishing v0.2.10 (all five artifacts). **v0.2.9 and v0.2.10
-  are published**; v0.2.4–v0.2.8 tags have no artifacts. Verify the CI path on the next tag. PLAN.md + ADRs 0007–0010 still describe the intended UX.
+  are published**; v0.2.4–v0.2.8 tags have no artifacts. Verify the CI path on the next tag.
+- **Host disk full (2026-10-31):** the v0.2.11 tag build created release id 27 and logged the
+  uploads, but they failed with `HTTP 500 Attachments.Save: write … no space left on device`
+  (`/dev/mapper/pve-vm--500--disk--0`, 7.8G, 100%, 0 free). The empty v0.2.11 release was
+  deleted so "latest" is v0.2.10 (5 assets). `publish_release.sh` now checks the HTTP code and
+  verifies the asset count, so this cannot look successful again. Host cleanup needs root on
+  192.168.88.30: `sudo journalctl --vacuum-size=100M` (journal is 837 MB), `sudo apt-get clean`
+  (91 MB), clear `/var/lib/gitea/data/attachments/tmp`. SSH works as `zwitschi` but `sudo -n`
+  requires a password. v0.2.11 artifacts are built locally in `build/` and can be uploaded by
+  running `./tools/publish_release.sh 0.2.11` once space is available. PLAN.md + ADRs 0007–0010 still describe the intended UX.
 - **Release v0.2.1 is LIVE** (2026-10-31): CI run 1110 built the NSIS installer + AppImage
   and published — installers/AppImage are on the releases page. Releasing = bump version → tag → push.
 - NSIS gotchas (validated in a local ubuntu:24.04 docker repro): makensis uses `-D` defines