feat: wait for healthy services and fill the job context (#1107)

Service containers were started and then left alone, so a job's first step could run while a database was still starting up. The runner now waits for every service whose image or `options` declare a healthcheck, as GitHub does. An unhealthy service fails the job with its container log, one that never becomes healthy fails it after `container.service_ready_timeout` (default `5m`, negative disables the wait), and one that exits without a healthcheck only gets its log and a warning.

The started containers also fill the `job` context, whose fields existed but were never populated: `job.container.{id,network}` and `job.services.<id>.{id,network,ports}`. `ports` is keyed by the plain container port, so `job.services.postgres.ports['5432']` resolves to the host port Docker picked.

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Co-authored-by: silverwind <me@silverwind.io>
Reviewed-on: https://gitea.com/gitea/runner/pulls/1107
Reviewed-by: silverwind <2021+silverwind@noreply.gitea.com>
Co-authored-by: bircni <bircni@icloud.com>

internal/pkg/config/config.example.yaml

@@ -226,6 +226,9 @@ container:
   # from the DinD daemon's filesystem. When enabled, ensure the workspace parent
   # directory is also mounted into the runner container and listed in valid_volumes.
   bind_workdir: false
+  # How long a job waits for a service container that declares a healthcheck to become
+  # healthy. A negative value (e.g. -1s) starts the steps without waiting.
+  service_ready_timeout: 5m
 
 host:
   # The parent directory of a job's working directory.

internal/pkg/config/config.go

@@ -92,6 +92,7 @@ type Container struct {
 	RequireDocker        bool                          `yaml:"require_docker"`         // Always require a reachable docker daemon, even if not required by runner
 	DockerTimeout        time.Duration                 `yaml:"docker_timeout"`         // Timeout to wait for the docker daemon to be reachable, if docker is required by require_docker or runner
 	BindWorkdir          bool                          `yaml:"bind_workdir"`           // BindWorkdir binds the workspace to the host filesystem instead of using Docker volumes. Required for DinD when jobs use docker compose with bind mounts.
+	ServiceReadyTimeout  time.Duration                 `yaml:"service_ready_timeout"`  // ServiceReadyTimeout bounds how long a job waits for a service container that declares a healthcheck to report healthy. Negative disables waiting.
 }
 
 type ContainerNetworkCreateOptions struct {