Pass `loglevel` to `cascade()` feed/sampler opens

Add `loglevel` param to both `maybe_open_feed()` and
`open_sample_stream()` calls in FSP engine's `cascade()` task to
ensure proper console log setup in downstream sampling tasks.

Deats,
- pass `loglevel=loglevel` to `maybe_open_feed()` call.
- pass `loglevel=loglevel` to `open_sample_stream()` call.

Also,
- switch to explicit kwargs: `fqmes=[fqme]` and `period_s=` for
  clarity and consistency with other callsites.

(this commit msg was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code

piker/fsp/_engine.py

@@ -484,7 +484,8 @@ async def cascade(
     # open a data feed stream with requested broker
     feed: Feed
     async with data.feed.maybe_open_feed(
-        [fqme],
+        fqmes=[fqme],
+        loglevel=loglevel,
 
         # TODO throttle tick outputs from *this* daemon since
         # it'll emit tons of ticks due to the throttle only
@@ -582,7 +583,8 @@ async def cascade(
                     # on every step msg received from the global `samplerd`
                     # service.
                     async with open_sample_stream(
-                        float(delay_s)
+                        period_s=float(delay_s),
+                        loglevel=loglevel,
                     ) as istream:
 
                         profiler(f'{func_name}: sample stream up')