feat(acp): migrate system/file Tauri commands to ACP+

Move `get_home_dir`, `save_exported_session_file`, `path_exists`,
`list_directory_entries`, `inspect_attachment_paths`,
`list_files_for_mentions` and `read_image_attachment` from the goose2
Tauri shell into a new `goose::system_ops` module exposed over ACP+ via
the `_goose/system/*` namespace. The desktop shell now opens save dialogs
via the Tauri JS `@tauri-apps/plugin-dialog` plugin and persists the
chosen file via a generic `_goose/system/write_file` ACP method.

The Tauri shell drops its `base64`, `dirs`, `ignore`, and `mime_guess`
dependencies along with the migrated commands, keeping the shell layer
thin per the goose2 architecture rule. Existing system_ops behaviour is
exercised through ported unit tests under `crates/goose/src/system_ops.rs`.

Closes #8692

Co-Authored-By: Oz <oz-agent@warp.dev>
Signed-off-by: Oz <oz-agent@warp.dev>

Author: oz-agent

Cargo.lock

@@ -647,6 +647,144 @@ pub struct ProviderInventoryEntryDto {
 #[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcResponse)]
 pub struct EmptyResponse {}
 
+/// Resolve the current user's home directory.
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcRequest)]
+#[request(method = "_goose/system/home_dir", response = GetHomeDirResponse)]
+#[serde(rename_all = "camelCase")]
+pub struct GetHomeDirRequest {}
+
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcResponse)]
+#[serde(rename_all = "camelCase")]
+pub struct GetHomeDirResponse {
+    /// Absolute path to the user's home directory.
+    pub path: String,
+}
+
+/// Check whether a path exists on disk.
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcRequest)]
+#[request(method = "_goose/system/path_exists", response = PathExistsResponse)]
+#[serde(rename_all = "camelCase")]
+pub struct PathExistsRequest {
+    pub path: String,
+}
+
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcResponse)]
+#[serde(rename_all = "camelCase")]
+pub struct PathExistsResponse {
+    pub exists: bool,
+}
+
+/// A single filesystem entry surfaced to the desktop UI.
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "camelCase")]
+pub struct FileTreeEntryDto {
+    pub name: String,
+    pub path: String,
+    /// `"file"` or `"directory"`.
+    pub kind: String,
+}
+
+/// List the immediate children of a directory.
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcRequest)]
+#[request(
+    method = "_goose/system/list_directory_entries",
+    response = ListDirectoryEntriesResponse
+)]
+#[serde(rename_all = "camelCase")]
+pub struct ListDirectoryEntriesRequest {
+    pub path: String,
+}
+
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcResponse)]
+#[serde(rename_all = "camelCase")]
+pub struct ListDirectoryEntriesResponse {
+    pub entries: Vec<FileTreeEntryDto>,
+}
+
+/// Metadata describing a single attachment path on disk.
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "camelCase")]
+pub struct AttachmentPathInfoDto {
+    pub name: String,
+    pub path: String,
+    /// `"file"` or `"directory"`.
+    pub kind: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub mime_type: Option<String>,
+}
+
+/// Inspect a batch of attachment paths. Missing entries are silently skipped.
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcRequest)]
+#[request(
+    method = "_goose/system/inspect_attachment_paths",
+    response = InspectAttachmentPathsResponse
+)]
+#[serde(rename_all = "camelCase")]
+pub struct InspectAttachmentPathsRequest {
+    pub paths: Vec<String>,
+}
+
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcResponse)]
+#[serde(rename_all = "camelCase")]
+pub struct InspectAttachmentPathsResponse {
+    pub attachments: Vec<AttachmentPathInfoDto>,
+}
+
+/// Walk one or more roots and return a sorted list of file paths suitable for
+/// `@`-mention pickers. Honours `.gitignore`, hidden files, and symlink escapes.
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcRequest)]
+#[request(
+    method = "_goose/system/list_files_for_mentions",
+    response = ListFilesForMentionsResponse
+)]
+#[serde(rename_all = "camelCase")]
+pub struct ListFilesForMentionsRequest {
+    pub roots: Vec<String>,
+    /// Maximum number of results to return. Clamped to 1..=5000; defaults to 1500.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub max_results: Option<u32>,
+}
+
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcResponse)]
+#[serde(rename_all = "camelCase")]
+pub struct ListFilesForMentionsResponse {
+    pub files: Vec<String>,
+}
+
+/// Read an image attachment from disk and return it as a base64 payload.
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcRequest)]
+#[request(
+    method = "_goose/system/read_image_attachment",
+    response = ReadImageAttachmentResponse
+)]
+#[serde(rename_all = "camelCase")]
+pub struct ReadImageAttachmentRequest {
+    pub path: String,
+}
+
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcResponse)]
+#[serde(rename_all = "camelCase")]
+pub struct ReadImageAttachmentResponse {
+    /// Base64-encoded image bytes.
+    pub base64: String,
+    /// MIME type detected from the path's extension (always starts with `image/`).
+    pub mime_type: String,
+}
+
+/// Write a UTF-8 string to a path on disk, creating any missing parents.
+///
+/// The desktop shell uses this to persist content the user has chosen via a
+/// native file dialog (e.g. exported sessions). Tauri-backed file dialogs are
+/// still owned by the desktop shell; only the actual write is delegated to
+/// `goose serve`.
+#[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcRequest)]
+#[request(method = "_goose/system/write_file", response = EmptyResponse)]
+#[serde(rename_all = "camelCase")]
+pub struct WriteFileRequest {
+    pub path: String,
+    pub contents: String,
+}
+
 /// List available local Whisper models with their download status.
 #[derive(Debug, Default, Clone, Serialize, Deserialize, JsonSchema, JsonRpcRequest)]
 #[request(

crates/goose-sdk/src/custom_requests.rs

@@ -193,6 +193,7 @@ sec1 = { version = "0.7", default-features = false, features = ["der", "pkcs8"],
 goose-acp-macros = { path = "../goose-acp-macros" }
 tower-http = { workspace = true, features = ["cors"] }
 http-body-util = "0.1.3"
+mime_guess = "2"
 
 
 [target.'cfg(target_os = "windows")'.dependencies]

crates/goose/Cargo.toml

@@ -194,6 +194,41 @@
       "method": "_goose/dictation/model/select",
       "requestType": "DictationModelSelectRequest",
       "responseType": "EmptyResponse"
+    },
+    {
+      "method": "_goose/system/home_dir",
+      "requestType": "GetHomeDirRequest",
+      "responseType": "GetHomeDirResponse"
+    },
+    {
+      "method": "_goose/system/path_exists",
+      "requestType": "PathExistsRequest",
+      "responseType": "PathExistsResponse"
+    },
+    {
+      "method": "_goose/system/list_directory_entries",
+      "requestType": "ListDirectoryEntriesRequest",
+      "responseType": "ListDirectoryEntriesResponse"
+    },
+    {
+      "method": "_goose/system/inspect_attachment_paths",
+      "requestType": "InspectAttachmentPathsRequest",
+      "responseType": "InspectAttachmentPathsResponse"
+    },
+    {
+      "method": "_goose/system/list_files_for_mentions",
+      "requestType": "ListFilesForMentionsRequest",
+      "responseType": "ListFilesForMentionsResponse"
+    },
+    {
+      "method": "_goose/system/read_image_attachment",
+      "requestType": "ReadImageAttachmentRequest",
+      "responseType": "ReadImageAttachmentResponse"
+    },
+    {
+      "method": "_goose/system/write_file",
+      "requestType": "WriteFileRequest",
+      "responseType": "EmptyResponse"
     }
   ]
 }