refactor: 退役 Vm epoch 字段面与 doc epoch 表述

crates/oxide_vm/src/vm/mod.rs

@@ -21,7 +21,7 @@ use crate::vm_debug;
 use crate::vm_state::{GcState, IterState, ProfilingState, SymbolState};
 use oxide_kernel::kernel::{KernelCore, KernelSession};
 use oxide_types::error::JsErrorKind;
-use oxide_types::mem::{Epoch, P};
+use oxide_types::mem::P;
 use oxide_types::object::{Cell, JsObject, NativeFnPtr};
 use oxide_types::private_key::INT_KEY_COUNT;
 use oxide_types::value::JsValue;
@@ -179,7 +179,6 @@ pub struct Vm {
     /// KernelCore 不重建），属性 get/set 热路径免每次 intern（hash64 + DashMap +
     /// RwLock 读锁）。
     pub(crate) length_si: u32,
-    pub epoch: Epoch,
     pub object_prototype: P<JsObject>,
     /// `%GeneratorPrototype%`：生成器实例的原型（next/return/throw 方法挂此）。
     pub generator_proto: P<JsObject>,
@@ -456,11 +455,6 @@ impl Vm {
         self.pc_watch = path;
     }
 
-    /// 只读访问 VM 的 epoch arena。
-    pub fn epoch(&self) -> &Epoch {
-        &self.epoch
-    }
-
     /// 若 `val` 是字符串，返回其内容的 `String` 副本；否则返回 `None`。
     pub fn lookup_str(&self, val: JsValue) -> Option<String> {
         if !val.is_string() {

crates/oxide_vm/src/vm/vmhost.rs

@@ -3,7 +3,6 @@
 use std::sync::Arc;
 
 use oxide_kernel::kernel::{KernelCore, KernelSession};
-use oxide_types::mem::Epoch;
 use oxide_types::object::{Cell, JsObject, PropAttributes};
 use oxide_types::value::JsValue;
 
@@ -46,9 +45,6 @@ impl oxide_runtime_api::VmHost for Vm {
     fn session(&self) -> &KernelSession {
         self.session()
     }
-    fn epoch(&self) -> &Epoch {
-        self.epoch()
-    }
     fn pc(&self) -> usize {
         self.pc
     }

crates/oxide_vm/src/vm_support.rs

@@ -11,7 +11,7 @@ use crate::vm_info;
 use crate::vm_state::{GcState, IterState, ProfilingState, SymbolState};
 use oxide_kernel::kernel::{KernelConfig, KernelCore, KernelSession};
 use oxide_kernel::shape_forge::EMPTY_SHAPE_ID;
-use oxide_types::mem::{Epoch, P};
+use oxide_types::mem::P;
 use oxide_types::object::{JsObject, JsString, PropAttributes};
 use oxide_types::value::JsValue;
 
@@ -55,7 +55,6 @@ impl Vm {
             kernel_core: core,
             session,
             length_si,
-            epoch: Epoch::new(),
             object_prototype: obj_proto,
             generator_proto: P::new(JsObject::new_empty(EMPTY_SHAPE_ID, JsValue::null())),
             generator_function_proto: P::new(JsObject::new_empty(EMPTY_SHAPE_ID, JsValue::null())),
@@ -189,7 +188,6 @@ impl Vm {
             kernel_core: core,
             session,
             length_si,
-            epoch: Epoch::new(),
             object_prototype: obj_proto,
             generator_proto: P::new(JsObject::new_empty(EMPTY_SHAPE_ID, JsValue::null())),
             generator_function_proto: P::new(JsObject::new_empty(EMPTY_SHAPE_ID, JsValue::null())),