Adds .forgejo/workflows/shell-lint.yml (pinned shellcheck v0.11.0 + sha256, -x,
default severity, fail on any finding, not path-filtered) and drives all 26
scripts to zero findings.
Two defects shellcheck cannot see:
render-secrets.sh left DECRYPTED vault contents in /tmp whenever a sops decrypt
failed -- the caller's set -e aborted the function before either cleanup ran.
Now removed on every exit path, with `|| return 1` on both sops calls so a
decrypt failure can never write a partial /etc/thermograph.env regardless of the
caller's shell options. Explicitly not a `trap ... RETURN`: such a trap set in a
sourced function persists into the caller's shell and re-fires when the caller's
next `.`/source completes, where the function-local tmp is unset -- fatal and
silent under deploy.sh's set -u. The file now records that reasoning.
autoscale.sh ran `set -eu` without pipefail while piping docker stats into awk,
so a failed left side was swallowed and the loop autoscaled on empty input.
Promoted to pipefail with a missed sample treated as a skip; verified busybox ash
in docker:27-cli supports it.
Also: capture-fixtures.sh's `jq . || cat` ran cat after jq had consumed stdin,
silently writing truncated fixtures; deploy.sh/deploy-stack.sh `# shellcheck
source=` paths corrected for the monorepo layout.
