woodpecker: add jellyfin-ha-src CI ServiceAccount (#352)

## Why

The jellyfin-ha-src Woodpecker build+test pipeline sets a `serviceAccountName`
that must exist in the `woodpecker` namespace.

## How

- Add a `jellyfin-ha-src` ServiceAccount under `apps/base/woodpecker/`,
  mirroring the `kea-operator-ci` build/test account (no Vault binding needed;
  the pipeline only restores/builds/tests).
- Register it in the woodpecker kustomization.

Reviewed-on: #352
Co-authored-by: Ben Vincent <ben@unkin.net>
Co-committed-by: Ben Vincent <ben@unkin.net>

apps/base/woodpecker/kustomization.yaml

@@ -8,6 +8,7 @@ resources:
   - cnpg_backup.yaml
   - cnpg_pooler.yaml
   - serviceaccount_kea_operator_ci.yaml
+  - serviceaccount_jellyfin_ha_src.yaml
   - serviceaccount_terraform_artifactapi.yaml
   - serviceaccount_terraform_authentik.yaml
   - serviceaccount_terraform_enc.yaml

apps/base/woodpecker/serviceaccount_jellyfin_ha_src.yaml

@@ -0,0 +1,6 @@
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: jellyfin-ha-src
+  namespace: woodpecker