Harden pod and container security contexts across all workloads

Add securityContext hardening (runAsNonRoot, readOnlyRootFilesystem,
capabilities drop ALL, allowPrivilegeEscalation false) to the 10 workloads
that lacked it: apache-tika, cyberchef, gotenberg, homeassistant,
matrix-delegation-nginx, paperless-server, paperless-consume cronjob
(plus automountServiceAccountToken false), patchmon-frontend,
urlaubsverwaltung and zipline. All contexts are configurable via
securityContext.pod / securityContext.container in values.yaml; writable
paths are provided as emptyDirs. Image-forced deviations (Home Assistant
root start for s6-overlay + NET_RAW for discovery, paperless root init
container for /run ownership) are documented in the charts' values.yaml.
Major version bump for every changed published chart.

urlaubsverwaltung/values.yaml

@@ -7,6 +7,21 @@ ingress:
   domain: null
 
 urlaubsverwaltung:
+  # The official image is built with Cloud Native Buildpacks and runs as the
+  # non-root cnb user (uid 1002, gid 1001). /tmp is a writable emptyDir for
+  # the JVM's temp/work files.
+  securityContext:
+    pod:
+      runAsNonRoot: true
+      runAsUser: 1002
+      runAsGroup: 1001
+    container:
+      allowPrivilegeEscalation: false
+      readOnlyRootFilesystem: true
+      runAsNonRoot: true
+      capabilities:
+        drop:
+          - ALL
   resources:
     requests:
       cpu: 0.1