docs(sdk): clarify pluginRoot scope for runtime plugins — #285 (activation-context: ActivateContext n'expose ni répertoire d'installation ni racine package ni file URL; commands-and-feedback + services: runCommand project/workspace-scoped, aucune résolution package-relative des scripts packagés; manifest: substitution ${pluginRoot}/${appDataDir} étendue par l'hôte uniquement dans contributes.mcpServers command/args/env/cwd; QA verte: npm run build, cohérence champs vs types SDK vérifiée)

docs/services.md

@@ -37,6 +37,13 @@ Key APIs:
 Use `runCommand()` only after preconditions are satisfied. `ownerAgentId` must be
 a real agent id when work belongs to an agent workflow.
 
+`runCommand()` is project/workspace scoped. Its `cwd` option is a relative path
+under the project root, and `command`/`args` are not resolved against the
+calling plugin's package. The SDK does not currently provide a public
+`pluginRoot` or package-path resolver for runtime command handlers. Packaged
+scripts cannot be launched through `runCommand()` by referring to their
+package-relative path.
+
 ## Tooling
 
 `services.tooling.diagnose()` checks executables, environment values and files