feat(sdk,plugins): API publique d'accès fichiers/workspace + analyse structure (#124,#129)

crates/domain/src/events.rs

@@ -366,6 +366,15 @@ pub enum DomainEvent {
         /// The project.
         project_id: ProjectId,
     },
+    /// A file under a project workspace changed through a public plugin workspace API.
+    PluginWorkspaceFileChanged {
+        /// The owning project.
+        project_id: ProjectId,
+        /// Normalized path relative to the project root.
+        path: String,
+        /// Public operation label, for example `changed`.
+        operation: String,
+    },
     /// An orchestrator request (dropped under `.ideai/requests/`) was processed
     /// by IdeA on behalf of a requester agent (ARCHITECTURE §14.3). Relayed so the
     /// frontend can surface orchestration activity; the resulting cell/tab opens

crates/domain/src/ports.rs

@@ -480,6 +480,17 @@ pub struct DirEntry {
     pub is_dir: bool,
 }
 
+/// Basic metadata returned by [`FileSystem::metadata`].
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct FileMetadata {
+    /// Whether the path points to a regular file.
+    pub is_file: bool,
+    /// Whether the path points to a directory.
+    pub is_dir: bool,
+    /// File length in bytes when known.
+    pub len: Option<u64>,
+}
+
 /// An owned, boxed stream of PTY output chunks.
 ///
 /// Concrete adapters decide the underlying transport; the domain only sees a
@@ -1281,6 +1292,12 @@ pub trait ProcessSpawner: Send + Sync {
     async fn run(&self, spec: SpawnSpec) -> Result<Output, ProcessError>;
 }
 
+/// Reads host environment variables through an injected adapter.
+pub trait EnvironmentReader: Send + Sync {
+    /// Returns one environment variable value, if present.
+    fn get(&self, name: &str) -> Option<String>;
+}
+
 /// Read a local structured CLI version using only the allowed `--version` probe.
 #[async_trait]
 pub trait CliVersionReader: Send + Sync {
@@ -1526,6 +1543,25 @@ pub trait FileSystem: Send + Sync {
     /// [`FsError`] on failure.
     async fn exists(&self, path: &RemotePath) -> Result<bool, FsError>;
 
+    /// Returns basic metadata for a path.
+    ///
+    /// The default keeps older remote/test adapters source-compatible. Concrete
+    /// adapters that can cheaply stat paths should override it.
+    ///
+    /// # Errors
+    /// [`FsError`] on failure.
+    async fn metadata(&self, path: &RemotePath) -> Result<FileMetadata, FsError> {
+        if self.exists(path).await? {
+            Ok(FileMetadata {
+                is_file: false,
+                is_dir: false,
+                len: None,
+            })
+        } else {
+            Err(FsError::NotFound(path.as_str().to_owned()))
+        }
+    }
+
     /// Removes a single file. A **missing** file is treated as success (idempotent
     /// delete), so this is safe to call best-effort.
     ///