fix: remove action feature flag and include execution (#9727)

# Which Problems Are Solved

Actions v2 is not a feature flag anymore, include functionality on
executions is not used and json tags of proto messages are handled
incorrectly.

# How the Problems Are Solved

- Remove actions from the feature flags on system and instance level
- Remove include type on executions, only in the API, later maybe in the
handling logic as well
- Use protojson in request and response handling of actions v2

# Additional Changes

- Correct integration tests for request and response handling
- Use json.RawMessage for events, so that the event payload is not
base64 encoded
- Added separate context for async webhook calls, that executions are
not cancelled when called async

# Additional Context

Related to #9759 
Closes #9710

---------

Co-authored-by: Livio Spring <livio.a@gmail.com>

internal/repository/execution/queue.go

@@ -41,16 +41,16 @@ func ContextInfoFromRequest(e *Request) *ContextInfoEvent {
 }
 
 type ContextInfoEvent struct {
-	AggregateID   string `json:"aggregateID,omitempty"`
-	AggregateType string `json:"aggregateType,omitempty"`
-	ResourceOwner string `json:"resourceOwner,omitempty"`
-	InstanceID    string `json:"instanceID,omitempty"`
-	Version       string `json:"version,omitempty"`
-	Sequence      uint64 `json:"sequence,omitempty"`
-	EventType     string `json:"event_type,omitempty"`
-	CreatedAt     string `json:"created_at,omitempty"`
-	UserID        string `json:"userID,omitempty"`
-	EventPayload  []byte `json:"event_payload,omitempty"`
+	AggregateID   string          `json:"aggregateID,omitempty"`
+	AggregateType string          `json:"aggregateType,omitempty"`
+	ResourceOwner string          `json:"resourceOwner,omitempty"`
+	InstanceID    string          `json:"instanceID,omitempty"`
+	Version       string          `json:"version,omitempty"`
+	Sequence      uint64          `json:"sequence,omitempty"`
+	EventType     string          `json:"event_type,omitempty"`
+	CreatedAt     string          `json:"created_at,omitempty"`
+	UserID        string          `json:"userID,omitempty"`
+	EventPayload  json.RawMessage `json:"event_payload,omitempty"`
 }
 
 func (c *ContextInfoEvent) GetHTTPRequestBody() []byte {