It was becoming too much with all the labels and markers and lines..
Might as well package it all together instead of cramming it in the
order mode loop, chief.
The techincal summary,
- move `_lines.position_line()` -> `PositionInfo.position_line()`.
- slap a `.pp` on the order mode instance which *is* a `PositionInfo`
- drop the position info info label for now (let's see what users want
eventually but for now let's keep it super minimal).
- add a `LevelMarker` type to replace the old `LevelLine` internal
marker system (includes ability to change the style and level on the
fly).
- change `_annotate.mk_marker()` -> `mk_maker_path()` and expect caller
to wrap in a `QGraphicsPathItem` if needed.
Generate and maintain position messages in the paper engine for each
`pikerd` session. We no longer tear down the engine on each client
disconnect. Ensure -ve size on sells to make the math work.
Add a new type/api to manage "contents labels" (labels that sit in
a view and display info about viewed data) since it's mostly used by
the linked charts cursor. Make `LinkedSplits.cursor` the new and only
instance var for the cursor such that charts can look it up from that
common class. Drop the `ChartPlotWidget._ohlc` array, just add
a `'ohlc'` entry to `._arrays`.
Orders in order mode should be chart oriented since there's a mode per
chart. If you want all orders just ask the ems or query all the charts
in a loop.
This fixes cancel-all-orders such that when 'cc' is tapped only the
orders on the *current* chart are cancelled, lel.
Generalize the methods for cancelling groups of orders (all or those
under cursor) and add new group status support such that statuses for
each cancel or order submission is displayed in the status bar. In the
"cancel-all-orders" case, use the new group status stuff.