zipline: NOTES.txt and the exponential-quantity fix (7.1.0+up4.7.0)

Part of #43 — templates/NOTES.txt.

The rule from the approved plan was that a NOTES.txt repeating the values is
worthless, so this one prints what an operator would otherwise look up in the
templates: the rendered URL (or the port-forward command when the Ingress is
off, plus the reason ingress.domain stays required — it is
CORE_DEFAULT_DOMAIN), the two op:// refs together with the exact field names
the 1Password items must carry ("connection-url" and "server-secret", because
the operator names the Secret keys after the item's fields), and the traps of
this chart: the setup page hands the super administrator to whoever reaches
the URL first, migrations run inside the startup probe's window (computed
from the effective probe values), a database outage leaves the pod running
and NotReady because liveness deliberately uses "/", the upload ceiling that
actually bites is the Ingress annotation and not the app's fixed 500mb, /tmp
is an emptyDir counted against the ephemeral-storage limit (computed) so an
oversized upload evicts the pod, and the uploads PVC is an ordinary release
resource that "helm uninstall" deletes. Conditional sections cover scaleDown
/ replicas: 0, more than one replica against the single ReadWriteOnce claim,
and a set zipline.env. No domain is baked into the chart; every host is
rendered from the values, examples use example.com.

Part of #157 — multiplyQuantity.

The null-safe fallbacks pass values through fromYaml, which parses every
number as float64, and Go's "%v" switches float64 to exponential notation
from about 1e6 upwards: a bare "1048576" arrived as "1.048576e+06" and the
render aborted on the suffix check. This is the canonical correction agreed
for all charts, taken over verbatim with this chart's prefix — the input and
the non-integer product now go through a formatNumber helper, and the
toYaml/fromYaml round trip is not touched, since it is not the cause.

Measured against ci/zipline/test-values.yaml on the chart's only resources
path, zipline.resources: before, both requests.memory=1048576 and
requests.ephemeralStorage=1048576 aborted with
  unsupported resource quantity suffix "e+06" in "1.048576e+06"
after, they render with the limits "3145728", while the 65536 fallback probe
still yields 196608 unchanged. Rendered manifests are byte-identical to the
previous version for the default values.

zipline/templates/_helpers.tpl

@@ -67,7 +67,7 @@ Handles plain numbers ("2", "0.5", 1073741824), decimal ("1.5Gi"), binary
 results are printed without a decimal point.
 */}}
 {{- define "zipline.multiplyQuantity" -}}
-{{- $quantity := printf "%v" .quantity -}}
+{{- $quantity := include "zipline.formatNumber" .quantity -}}
 {{- $number := regexFind "^[0-9]+(\\.[0-9]+)?" $quantity -}}
 {{- if not $number -}}
 {{- fail (printf "cannot parse resource quantity %q" $quantity) -}}
@@ -80,7 +80,24 @@ results are printed without a decimal point.
 {{- if eq $product (floor $product) -}}
 {{- printf "%d%s" (int64 $product) $suffix -}}
 {{- else -}}
-{{- printf "%v%s" $product $suffix -}}
+{{- printf "%s%s" (include "zipline.formatNumber" $product) $suffix -}}
+{{- end -}}
+{{- end -}}
+
+{{/*
+Render a number as a plain decimal string, never in exponential notation.
+
+Why this exists (issue #157): the null-safe fallback helpers pass values
+through fromYaml, which parses every number as float64. Go's "%v" switches
+float64 to exponential notation from about 1e6 upwards, so a bare byte count
+like 1048576 became "1.048576e+06" - not a valid Kubernetes quantity, and the
+render aborted. Strings ("512Mi") are passed through untouched.
+*/}}
+{{- define "zipline.formatNumber" -}}
+{{- if kindIs "float64" . -}}
+{{- regexReplaceAll "\\.?0+$" (printf "%.10f" .) "" -}}
+{{- else -}}
+{{- printf "%v" . -}}
 {{- end -}}
 {{- end -}}