deps: everything to latest stable

Python 3.12 -> 3.14, postgres 16 -> 18, uv 0.5.11 -> 0.11.29,
trivy 0.58.1 -> 0.72.0, gitleaks 8.21.2 -> 8.30.1, yq 4.44.6 -> 4.53.3,
and every action re-pinned to the SHA of its latest tag (checkout v7,
setup-uv v8, buildx v4, login v4, hadolint v3.3.0). helm stays 3.21.3:
already current for 3.x, and helm 4 is a breaking change, not a CVE fix.

trivy mattered most. A vulnerability scanner fourteen minor versions behind is
the one stale pin that hides all the others.

ruff target-version is deliberately py313 while the runtime is 3.14. It
controls the syntax the formatter may emit, and at py314 it rewrites
'except (A, B):' into PEP 758's unparenthesized form — which reads exactly
like Python 2's 'except E, name:' and is a hard SyntaxError below 3.14. No
semantic gain, real readability cost, in a repo meant to be read.

Verified on 3.14: ruff, ruff format, mypy --strict, 166 tests, helm lint,
bandit, pip-audit. The digest guard still rejects placeholder digests.

Risk carried knowingly: the bumped actions run on node24. If act_runner only
provides node20, every job fails at action startup and this commit is the
revert.

scripts/bump-digests.sh

@@ -37,8 +37,8 @@ trap cleanup EXIT
 #
 # Not python+pyyaml: a yaml round-trip strips every comment in values.yaml, and those
 # comments are the only thing explaining why the digests are there. yq edits in place.
-YQ_VERSION="4.44.6"
-YQ_SHA256="9477ac3cc447b6c083986129e35af8122eb2b938fe55c9c3e40436fb966e5813"
+YQ_VERSION="4.53.3"
+YQ_SHA256="578648e463a11c1b6db6010cbf41eafed6bee79466fcffa1bb446672cf7945ea"
 
 ensure_yq() {
     if command -v yq >/dev/null 2>&1; then