내부 filesystem observation/invalidation (MCP fs/watch 없음)

crates/runner/Cargo.toml

@@ -19,6 +19,7 @@ sha2 = "0.10"
 hex = "0.4"
 libc = "0.2"
 tokio = { version = "1", features = ["macros", "rt-multi-thread", "process", "time", "io-util", "net", "sync"] }
+notify = "8"
 
 [dev-dependencies]
 tempfile = "3"

crates/runner/src/apply.rs

@@ -10,6 +10,7 @@ use crate::PathSandbox;
 impl InProcessRunner {
     pub async fn read_file(&self, ws: &Workspace, path: &str) -> Result<ReadResult, ErrorBody> {
         ws.require_file_read()?;
+        self.touch_watch(ws);
         PathSandbox::new(ws.clone()).read_file(path).await
     }
 
@@ -19,11 +20,13 @@ impl InProcessRunner {
         glob: Option<&str>,
     ) -> Result<FindResult, ErrorBody> {
         ws.require_file_read()?;
+        self.touch_watch(ws);
         PathSandbox::new(ws.clone()).find(glob).await
     }
 
     pub async fn file_version(&self, ws: &Workspace, path: &str) -> Result<String, ErrorBody> {
         ws.require_file_read()?;
+        self.touch_watch(ws);
         PathSandbox::new(ws.clone()).version(path).await
     }
 
@@ -33,6 +36,7 @@ impl InProcessRunner {
         req: RunnerApplyPatchRequest,
     ) -> Result<RunnerApplyPatchResult, ErrorBody> {
         ws.require_file_write()?;
+        self.touch_watch(ws);
         let sandbox = PathSandbox::new(ws.clone());
         for (path, expected) in &req.expected_versions {
             let actual = sandbox.version(path).await?;

crates/runner/src/lib.rs

@@ -109,6 +109,7 @@ mod process;
 mod rollback;
 mod socket;
 mod uds;
+mod watch;
 mod wire;
 
 pub use api::{
@@ -135,6 +136,7 @@ pub use socket::{
     runner_socket_path, RUNNER_SOCKET_NAME,
 };
 pub use uds::{DisconnectHook, UdsRunner, RUNNER_CALL_DEADLINE};
+pub use watch::{FsWatchEvent, FsWatchKind, WatchClosed, WatchSubscription};
 pub use wire::{
     host_worker, read_frame, serve_runner_connection, write_frame, RunnerEvent, RunnerOp,
     RunnerOpResult, WireEnvelope, WireKind, WIRE_PROTOCOL,