Update documentation for inactivity_timeout duration string support

Co-authored-by: tobio <[email protected]>

Author: Copilot

docs/resources/fleet_agent_policy.md

@@ -51,7 +51,7 @@ resource "elasticstack_fleet_agent_policy" "test_policy" {
 - `download_source_id` (String) The identifier for the Elastic Agent binary download server.
 - `fleet_server_host_id` (String) The identifier for the Fleet server host.
 - `global_data_tags` (Attributes Map) User-defined data tags to apply to all inputs. Values can be strings (string_value) or numbers (number_value) but not both. Example -- key1 = {string_value = value1}, key2 = {number_value = 42} (see [below for nested schema](#nestedatt--global_data_tags))
-- `inactivity_timeout` (Number) The inactivity timeout (in seconds) for the agent policy. If an agent does not report within this time period, it will be considered inactive.
+- `inactivity_timeout` (String) The inactivity timeout for the agent policy. If an agent does not report within this time period, it will be considered inactive. Supports duration strings (e.g., '30s', '2m', '1h').
 - `monitor_logs` (Boolean) Enable collection of agent logs.
 - `monitor_metrics` (Boolean) Enable collection of agent metrics.
 - `monitoring_output_id` (String) The identifier for monitoring output.