Implement container logs handler

- Add Docker client to handlers for container operations
- Implement HandleAppLogs() to fetch and return container logs
- Support ?tail=N query parameter (default 500 lines)
- Handle missing container gracefully

internal/handlers/handlers.go

@@ -9,6 +9,7 @@ import (
 	"go.uber.org/fx"
 
 	"git.eeqj.de/sneak/upaas/internal/database"
+	"git.eeqj.de/sneak/upaas/internal/docker"
 	"git.eeqj.de/sneak/upaas/internal/globals"
 	"git.eeqj.de/sneak/upaas/internal/healthcheck"
 	"git.eeqj.de/sneak/upaas/internal/logger"
@@ -30,6 +31,7 @@ type Params struct {
 	App         *app.Service
 	Deploy      *deploy.Service
 	Webhook     *webhook.Service
+	Docker      *docker.Client
 }
 
 // Handlers provides HTTP request handlers.
@@ -42,6 +44,7 @@ type Handlers struct {
 	appService *app.Service
 	deploy     *deploy.Service
 	webhook    *webhook.Service
+	docker     *docker.Client
 }
 
 // New creates a new Handlers instance.
@@ -55,6 +58,7 @@ func New(_ fx.Lifecycle, params Params) (*Handlers, error) {
 		appService: params.App,
 		deploy:     params.Deploy,
 		webhook:    params.Webhook,
+		docker:     params.Docker,
 	}, nil
 }