docs: document script hot-reload mechanisms for all script types

docs/requirements/Component-SiteRuntime.md

@@ -209,6 +209,32 @@ When the Instance Actor is stopped (due to disable, delete, or redeployment), Ak
 
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+## Script Lifecycle
+
+All script types can be updated without restarting the cluster, but the mechanism differs per type.
+
+### Instance Scripts and Alarm On-Trigger Scripts
+
+- Compiled at deployment time when the Deployment Manager receives a flattened configuration and creates the Instance Actor hierarchy.
+- **To update**: modify the script in the template, then redeploy the instance (`instance deploy --id <N>`).
+- Redeployment stops the existing Instance Actor and all its children, creates a new Instance Actor, and recompiles all scripts and alarms from the updated configuration.
+- There is no way to hot-reload a single instance script without redeploying the entire instance.
+
+### Shared Scripts
+
+- Compiled at the site when received from central via artifact deployment (`deploy artifacts`).
+- The `SharedScriptLibrary` replaces its in-memory compiled code dictionary under a lock, making updated code immediately available to all Script Actors.
+- **To update**: modify the shared script via the CLI or UI, then run `deploy artifacts` to push the change to sites.
+- No instance redeployment is required — running instances pick up the new shared script code on the next `Scripts.CallShared()` invocation.
+
+### Inbound API Method Scripts
+
+- See Component-InboundAPI.md for the compilation and hot-reload lifecycle of API method scripts.
+
+> **Warning**: Editing scripts via direct SQL does not trigger recompilation. The in-memory compiled script will remain stale until the next node restart or redeployment. Always use the CLI, Management API, or Central UI to modify scripts.
+
+---
+
 ## Script Runtime API
 
 Available to all Script Execution Actors and Alarm Execution Actors: