Adjust to `trio`'s strict eg nurseries throughout!

Using `tractor.trionics.collapse_eg()` as needed to avoid, at the least,
crash-worthy (in debug-mode REPL-ing terms) nested cancellation egs that
exhibit on SIGINT/ctl-c of each "app" (chart & daemon).

Also a bit of renaming of all `trio.Nursery`s to `tn`, the new "task
nursery" shorthand-var-name being used in all our other `tractor`
related projects.

piker/brokers/_daemon.py

@@ -96,7 +96,10 @@ async def _setup_persistent_brokerd(
     # - `open_symbol_search()`
     # NOTE: see ep invocation details inside `.data.feed`.
     try:
-        async with trio.open_nursery() as service_nursery:
+        async with (
+            tractor.trionics.collapse_eg(),
+            trio.open_nursery() as service_nursery
+        ):
             bus: _FeedsBus = feed.get_feed_bus(
                 brokername,
                 service_nursery,

piker/clearing/_client.py

@@ -25,7 +25,10 @@ from typing import TYPE_CHECKING
 
 import trio
 import tractor
-from tractor.trionics import broadcast_receiver
+from tractor.trionics import (
+    broadcast_receiver,
+    collapse_eg,
+)
 
 from ._util import (
     log,  # sub-sys logger
@@ -281,8 +284,11 @@ async def open_ems(
             client._ems_stream = trades_stream
 
             # start sync code order msg delivery task
-            async with trio.open_nursery() as n:
-                n.start_soon(
+            async with (
+                collapse_eg(),
+                trio.open_nursery() as tn,
+            ):
+                tn.start_soon(
                     relay_orders_from_sync_code,
                     client,
                     fqme,
@@ -298,4 +304,4 @@ async def open_ems(
                 )
 
                 # stop the sync-msg-relay task on exit.
-                n.cancel_scope.cancel()
+                tn.cancel_scope.cancel()

piker/fsp/_engine.py

@@ -498,6 +498,7 @@ async def cascade(
 
         func_name: str = func.__name__
         async with (
+            tractor.trionics.collapse_eg(),  # avoid multi-taskc tb in console
             trio.open_nursery() as tn,
         ):
             # TODO: might be better to just make a "restart" method where

piker/service/_actor_runtime.py

@@ -200,7 +200,8 @@ async def open_pikerd(
             reg_addrs,
         ),
         tractor.open_nursery() as actor_nursery,
-        trio.open_nursery() as service_nursery,
+        tractor.trionics.collapse_eg(),
+        trio.open_nursery() as service_tn,
     ):
         for addr in reg_addrs:
             if addr not in root_actor.accept_addrs:
@@ -211,7 +212,7 @@ async def open_pikerd(
 
         # assign globally for future daemon/task creation
         Services.actor_n = actor_nursery
-        Services.service_n = service_nursery
+        Services.service_n = service_tn
         Services.debug_mode = debug_mode
 
         try:
@@ -221,7 +222,7 @@ async def open_pikerd(
             # TODO: is this more clever/efficient?
             # if 'samplerd' in Services.service_tasks:
             #     await Services.cancel_service('samplerd')
-            service_nursery.cancel_scope.cancel()
+            service_tn.cancel_scope.cancel()
 
 
 # TODO: do we even need this?

piker/ui/_app.py

@@ -21,6 +21,7 @@ Main app startup and run.
 from functools import partial
 from types import ModuleType
 
+import tractor
 import trio
 
 from piker.ui.qt import (
@@ -116,6 +117,7 @@ async def _async_main(
         needed_brokermods[brokername] = brokers[brokername]
 
     async with (
+        tractor.trionics.collapse_eg(),
         trio.open_nursery() as root_n,
     ):
         # set root nursery and task stack for spawning other charts/feeds

piker/ui/_chart.py

@@ -33,7 +33,6 @@ import trio
 
 from piker.ui.qt import (
     QtCore,
-    QtWidgets,
     Qt,
     QLineF,
     QFrame,

piker/ui/_display.py

@@ -1445,7 +1445,10 @@ async def display_symbol_data(
         # for pause/resume on mouse interaction
         rt_chart.feed = feed
 
-        async with trio.open_nursery() as ln:
+        async with (
+            tractor.trionics.collapse_eg(),
+            trio.open_nursery() as ln,
+        ):
             # if available load volume related built-in display(s)
             vlm_charts: dict[
                 str,

piker/ui/_event.py

@@ -22,7 +22,10 @@ from contextlib import asynccontextmanager as acm
 from typing import Callable
 
 import trio
-from tractor.trionics import gather_contexts
+from tractor.trionics import (
+    gather_contexts,
+    collapse_eg,
+)
 
 from piker.ui.qt import (
     QtCore,
@@ -207,7 +210,10 @@ async def open_signal_handler(
         async for args in recv:
             await async_handler(*args)
 
-    async with trio.open_nursery() as tn:
+    async with (
+        collapse_eg(),
+        trio.open_nursery() as tn
+    ):
         tn.start_soon(proxy_to_handler)
         async with send:
             yield
@@ -242,6 +248,7 @@ async def open_handlers(
     widget: QWidget
     streams: list[trio.abc.ReceiveChannel]
     async with (
+        collapse_eg(),
         trio.open_nursery() as tn,
         gather_contexts([
             open_event_stream(

piker/ui/_fsp.py

@@ -600,6 +600,7 @@ async def open_fsp_admin(
             kwargs=kwargs,
         ) as (cache_hit, cluster_map),
 
+        tractor.trionics.collapse_eg(),
         trio.open_nursery() as tn,
     ):
         if cache_hit:
@@ -613,6 +614,8 @@ async def open_fsp_admin(
         )
         try:
             yield admin
+
+        # ??TODO, does this *need* to be inside a finally?
         finally:
             # terminate all tasks via signals
             for key, entry in admin._registry.items():

piker/ui/order_mode.py

@@ -792,6 +792,7 @@ async def open_order_mode(
             brokerd_accounts,
             ems_dialog_msgs,
         ),
+        tractor.trionics.collapse_eg(),
         trio.open_nursery() as tn,
 
     ):