feat: add per-container resource configuration for runner and DinD #160 (#168)

This a correction that is forf from original work of [anders.eficode](https://gitea.com/anders.eficode) on [pull request #160](https://gitea.com/gitea/helm-actions/pulls/160)
Description of the change
Adds statefulset.dind.resources and statefulset.runner.resources as optional per-container resource overrides. When set, each takes precedence over the shared statefulset.resources for that container. When unset (default {}), statefulset.resources is used as before.

Benefits
The DinD sidecar and the runner container have very different resource profiles — DinD is memory-hungry (image layer cache, concurrent builds, image pulls) while the runner is a lightweight coordinator that is mostly idle between jobs. Separate resource limits allow right-sizing each container independently, avoiding the choice between over-provisioning the runner or under-provisioning DinD.

Possible drawbacks
None. Fully backward-compatible — both new values default to {}, causing the shared statefulset.resources fallback to apply exactly as before.

Checklist
- [x] Parameters are documented in the `values.yaml` and added to the `README.md` using [readme-generator-for-helm](https://github.com/bitnami-labs/readme-generator-for-helm)
- [x] Breaking changes are documented in the `README.md`
- [x] Helm templating unittests are added (required when changing anything in `templates` folder)
- [x] Bash unittests are added (required when changing anything in `scripts` folder)
- [x] All added template resources MUST render a namespace in metadata

---------

Co-authored-by: Le Prévost-Corvellec Arnault <arnault.le.prevost.corvellec@carbon-it.com>
Co-authored-by: Anders <lantzanders@gmail.com>
Reviewed-on: https://gitea.com/gitea/helm-actions/pulls/168
Reviewed-by: DaanSelen <135789+daanselen@noreply.gitea.com>
Co-authored-by: Arnault_LPC <194310+arnault_lpc@noreply.gitea.com>

values.yaml

@@ -1,12 +1,15 @@
 # Configure Gitea Actions
 ## @section Gitea Actions
+## @descriptionStart
+## For resource limit examples (runner vs DinD), see [docs/resources.md](./docs/resources.md).
+## @descriptionEnd
 #
 ## @param enabled Create a Gitea Runner StatefulSet.
 ## @param statefulset.replicas the amount of (replica) runner pods deployed
 ## @param statefulset.timezone is the timezone that will be set in the runner image
 ## @param statefulset.annotations Gitea Runner annotations
 ## @param statefulset.labels Gitea Runner labels
-## @param statefulset.resources Gitea Runner resources
+## @param statefulset.resources Shared resource requests/limits for both containers. Overridden by statefulset.runner.resources and statefulset.dind.resources. See docs/resources.md.
 ## @param statefulset.nodeSelector NodeSelector for the statefulset
 ## @param statefulset.tolerations Tolerations for the statefulset
 ## @param statefulset.affinity Affinity for the statefulset
@@ -25,6 +28,7 @@
 ## @param statefulset.runner.digest Image digest. Allows to pin the given image tag. Useful for having control over mutable tags like `latest`
 ## @param statefulset.runner.pullPolicy The Gitea Runner pullPolicy
 ## @param statefulset.runner.fullOverride Completely overrides the image registry, path/image, tag and digest.
+## @param statefulset.runner.resources Resource requests/limits for the runner container. Takes precedence over statefulset.resources when set.
 ## @param statefulset.runner.extraVolumeMounts Allows mounting extra volumes in the Gitea Runner container
 ## @param statefulset.runner.extraEnvs Allows adding custom environment variables
 ## @param statefulset.runner.flushCache whether to clear the .runner (cache) file by creating an extra init container, can slightly increase boot-up time
@@ -38,6 +42,7 @@
 ## @param statefulset.dind.digest Image digest. Allows to pin the given image tag. Useful for having control over mutable tags like `latest`
 ## @param statefulset.dind.fullOverride Completely overrides the image registry, path/image, tag and digest.
 ## @param statefulset.dind.pullPolicy The Docker-in-Docker pullPolicy
+## @param statefulset.dind.resources Resource requests/limits for the DinD sidecar container. Takes precedence over statefulset.resources when set.
 ## @param statefulset.dind.extraVolumeMounts Allows mounting extra volumes in the Docker-in-Docker container
 ## @param statefulset.dind.extraEnvs Allows adding custom environment variables, such as `DOCKER_IPTABLES_LEGACY`
 ## @param statefulset.dind.extraArgs Allows adding custom arguments to the Docker Daemon
@@ -75,6 +80,7 @@ statefulset:
     digest: ""
     pullPolicy: IfNotPresent
     fullOverride: ""
+    resources: {}
     extraVolumeMounts: []
     extraEnvs:
       []
@@ -104,6 +110,7 @@ statefulset:
     digest: ""
     pullPolicy: IfNotPresent
     fullOverride: ""
+    resources: {}
     extraVolumeMounts: []
 
     # If the container keeps crashing in your environment, you might have to add the `DOCKER_IPTABLES_LEGACY` environment variable.