feat(files): add scoped local file editing over daemon IPC

Cargo.toml

@@ -6,6 +6,7 @@ members = [
   "crates/daemon",
   "crates/e2e",
   "crates/fake-agent",
+  "crates/file-metadata",
   "crates/git",
   "crates/session",
   "crates/storage",

apps/desktop/src/app/AppShell.test.tsx

@@ -1430,6 +1430,7 @@ describe("AppShell canvas workflows", () => {
       sessionId: stoppedSession.id,
       path: stoppedSession.worktreePath,
     });
+    let registeredWorktrees = [worktree];
     const client = createMockIpcClient({
       bootstrap: createBootstrap({
         projects: [project],
@@ -1438,7 +1439,7 @@ describe("AppShell canvas workflows", () => {
         worktrees: [worktree],
       }),
       handlers: {
-        listWorktrees: async () => [],
+        listWorktrees: async () => registeredWorktrees,
         stopSession: async () => ({
           ...runningSession,
           status: "exited",
@@ -1451,7 +1452,9 @@ describe("AppShell canvas workflows", () => {
           worktreeId: worktree.id,
           expiresAtMs: TEST_TIME + 60_000,
         }),
-        removeWorktree: async () => undefined,
+        removeWorktree: async () => {
+          registeredWorktrees = [];
+        },
       },
     });
     const user = await renderApp(client);

apps/desktop/src/ipc/client.ts

@@ -1,6 +1,15 @@
 import { decodeKnowledgeEntry, decodeKnowledgePage } from "./knowledge-schema";
 import { decodeKnowledgeDiscoverResponse, decodeKnowledgeReadResponse } from "./discovery-schema";
 import type { KnowledgeEntry, KnowledgeListRequest, KnowledgeListResponse, KnowledgeSaveRequest, KnowledgeDeleteRequest, KnowledgeDiscoverRequest, KnowledgeDiscoverResponse, KnowledgeReadRequest, KnowledgeReadResponse, WorktreeListRequest } from "./domain";
+import type {
+  FileListRequest,
+  FileListResponse,
+  FileReadRequest,
+  FileReadResponse,
+  FileWriteRequest,
+  FileWriteResponse,
+} from "./domain";
+import { decodeFileListResponse, decodeFileReadResponse, decodeFileWriteResponse } from "./file-schema";
 import { invoke } from "@tauri-apps/api/core";
 import { listen } from "@tauri-apps/api/event";
 import { openPath } from "@tauri-apps/plugin-opener";
@@ -64,6 +73,9 @@ export interface TerminalResizeInput {
 /** The sole frontend interface to daemon and native desktop capabilities. */
 export interface IpcClient {
   readonly platform: AppPlatform;
+  listFiles(input: FileListRequest): Promise<FileListResponse>;
+  readFile(input: FileReadRequest): Promise<FileReadResponse>;
+  writeFile(input: FileWriteRequest): Promise<FileWriteResponse>;
   listKnowledge(input: KnowledgeListRequest): Promise<KnowledgeListResponse>;
   saveKnowledge(input: KnowledgeSaveRequest): Promise<KnowledgeEntry>;
   deleteKnowledge(input: KnowledgeDeleteRequest): Promise<void>;
@@ -146,6 +158,18 @@ export function toIpcError(error: unknown): IpcError {
 class TauriIpcClient implements IpcClient {
   readonly platform = detectPlatform();
 
+  async listFiles(input: FileListRequest): Promise<FileListResponse> {
+    return this.fileRequest("file.list", input, (value) => decodeFileListResponse(value, input));
+  }
+
+  async readFile(input: FileReadRequest): Promise<FileReadResponse> {
+    return this.fileRequest("file.read", input, (value) => decodeFileReadResponse(value, input));
+  }
+
+  async writeFile(input: FileWriteRequest): Promise<FileWriteResponse> {
+    return this.fileRequest("file.write", input, (value) => decodeFileWriteResponse(value, input));
+  }
+
   async listKnowledge(input: KnowledgeListRequest): Promise<KnowledgeListResponse> {
     return decodeKnowledgePage(await this.request("knowledge.list", input));
   }
@@ -335,6 +359,14 @@ class TauriIpcClient implements IpcClient {
     }
   }
 
+  private async fileRequest<T>(method: string, payload: unknown, decode: (value: unknown) => T): Promise<T> {
+    try {
+      return decode(await this.request(method, payload));
+    } catch (error) {
+      throw toIpcError(error);
+    }
+  }
+
   private async request(method: string, payload: unknown): Promise<unknown> {
     const request = createRequestEnvelope(method, payload);
     try {

apps/desktop/src/ipc/domain.ts

@@ -1,6 +1,6 @@
 /** Additive daemon contracts. Existing UI DTOs remain owned by types.ts. */
 export type * from "./types";
-import type { Worktree } from "./types";
+import type { GitTarget, Worktree } from "./types";
 
 /** List managed worktrees; omission includes every registered project. */
 export interface WorktreeListRequest {
@@ -56,6 +56,68 @@ export interface KnowledgeDeleteRequest {
   readonly expectedRevision: number;
 }
 
+/** Registered project directory, session cwd, or managed worktree root. */
+export type FileTarget = GitTarget | {
+  readonly kind: "worktree";
+  readonly worktreeId: string;
+};
+/** Canonical padded base64 of relative Unix path bytes; empty means list root. */
+export type FilePath = string;
+/** Opaque v1 SHA-256 revision; preserve exactly as returned by the daemon. */
+export type FileRevision = string;
+
+export interface FileEntry {
+  readonly pathBase64: FilePath;
+  readonly displayName: string;
+  readonly kind: "file" | "directory" | "symlink" | "other";
+  readonly sizeBytes?: number;
+  readonly modifiedAtMs?: number;
+}
+
+export interface FileListRequest {
+  readonly target: FileTarget;
+  readonly pathBase64: FilePath;
+  readonly limit?: number;
+  readonly afterNameBase64?: string;
+}
+
+export interface FileListResponse {
+  readonly entries: readonly FileEntry[];
+  readonly nextAfterNameBase64?: string;
+  readonly observedAtMs: number;
+}
+
+export interface FileReadRequest {
+  readonly target: FileTarget;
+  readonly pathBase64: FilePath;
+}
+
+/** Text is bounded to 128 KiB UTF-8 including any BOM; line endings are preserved. */
+export interface FileReadResponse {
+  readonly pathBase64: FilePath;
+  readonly text: string;
+  readonly revision: FileRevision;
+  readonly sizeBytes: number;
+  readonly modifiedAtMs?: number;
+  readonly observedAtMs: number;
+}
+
+/** Existing regular text files only; stale revisions leave the buffer unsaved. */
+export interface FileWriteRequest {
+  readonly target: FileTarget;
+  readonly pathBase64: FilePath;
+  readonly text: string;
+  readonly expectedRevision: FileRevision;
+}
+
+export interface FileWriteResponse {
+  readonly pathBase64: FilePath;
+  readonly revision: FileRevision;
+  readonly sizeBytes: number;
+  readonly modifiedAtMs?: number;
+  readonly writtenAtMs: number;
+}
+
 /** Mirrors core::knowledge::discovery; discovery never establishes native activation. */
 export type KnowledgeSourceKind = "rule" | "skill";
 export type KnowledgeProvider = "codex" | "claude" | "cursor";