Major refactoring of Scheduler/Task

Highlights:
  * Suspended tasks no longer hog a thread and idle. Instead their
    thread ends and they are moved into a suspended vector inside the
    scheduler itself.
  * Tasks that start in a delayed state (e.g. forks) now no longer use
    a thread with a manual delay. Instead they begin their life in
    suspended state and are picked up by the scheduler tick.
  * Gut the remainder of the complicated dispatch logic that was
    leftover from the old async/tokio version of this code. Intermediate
    result objects (which used to be processed in batch) are gone, and
    actions are immediately acted on. This should be a lot easier to
    read now.

I believe this paves the way for a more testable, robust future.

crates/kernel/src/builtins/bf_server.rs

@@ -71,7 +71,6 @@ fn bf_notify(bf_args: &mut BfCallState<'_>) -> Result<BfRet, BfErr> {
         .map_err(world_state_bf_err)?;
 
     let event = NarrativeEvent::notify_text(bf_args.exec_state.caller(), msg.to_string());
-
     bf_args
         .scheduler_sender
         .send((
@@ -81,7 +80,7 @@ fn bf_notify(bf_args: &mut BfCallState<'_>) -> Result<BfRet, BfErr> {
                 event,
             },
         ))
-        .expect("scheduler is not listening");
+        .ok();
 
     // MOO docs say this should return none, but in reality it returns 1?
     Ok(Ret(v_int(1)))
@@ -444,7 +443,7 @@ fn bf_queued_tasks(bf_args: &mut BfCallState<'_>) -> Result<BfRet, BfErr> {
         .scheduler_sender
         .send((
             bf_args.exec_state.task_id,
-            SchedulerControlMsg::DescribeOtherTasks(send),
+            SchedulerControlMsg::RequestQueuedTasks(send),
         ))
         .expect("scheduler is not listening");
     let tasks = receive.recv().expect("scheduler is not listening");

crates/kernel/src/tasks/mod.rs

@@ -14,9 +14,6 @@
 
 use crate::tasks::scheduler::TaskResult;
 use moor_values::var::{List, Objid};
-use std::cell::Cell;
-use std::marker::PhantomData;
-use std::sync::MutexGuard;
 use std::time::SystemTime;
 
 pub mod command_parse;
@@ -42,9 +39,6 @@ impl TaskHandle {
     }
 }
 
-pub(crate) type PhantomUnsync = PhantomData<Cell<()>>;
-pub(crate) type PhantomUnsend = PhantomData<MutexGuard<'static, ()>>;
-
 /// The minimum set of information needed to make a *resolution* call for a verb.
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub struct VerbCall {