Improve module structure

[GDYendell]

• Add some tests for missing coverage

Fixes #253

Summary

Organise modules into directories with a small number of modules at the root, such as control_system, launch and tracer

• attributes
• controllers
• datatypes
• methods
• transport -> transports

Split most files with multiple classes into separate files

Update imports, patches and docs ignores

Rename some typevars

• T -> DType_T so that drivers can use T for general generic type hints without clashes

Rename Numerical -> Numeric

Import public APIs in __init__.pys to simplify import paths

Breaking Changes

• Rename from fastcs.datatypes import T -> from fastcs.datatypes import DType_T
• Imports
  • from fastcs.attribute_io -> from fastcs.attributes
  • from fastcs.attribute_io_ref -> from fastcs.attributes
  • from fastcs.controller -> from fastcs.controllers
  • from fastcs.cs_methods -> from fastcs.methods
  • from fastcs.transport -> from fastcs.transports
  • from fastcs.wrappers -> from fastcs.methods
  • from fastcs.attributes import ONCE -> from fastcs.util import ONCE
  • fastcs.transport.epics.options import EpicsGUIOptions, EpicsIOCOptions -> from fastcs.transports.epics import EpicsGUIOptions, EpicsIOCOptions
  • from fastcs.transport.epics.ca.transport import EpicsCATransport -> from fastcs.transports.epics.ca import EpicsCATransport

[GDYendell]

@shihab-dls the diff is huge, but there are hardly any actual code changes. Could you just have a scan through and see if you think where I have moved things around make sense, and that the imports are nicer?

[codecov]

Codecov Report

❌ Patch coverage is 97.56469% with 16 lines in your changes missing coverage. Please review.
✅ Project coverage is 90.37%. Comparing base (9d894ef) to head (75782d3).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/fastcs/controllers/controller_vector.py	87.87%	4 Missing ⚠️
src/fastcs/attributes/attr_r.py	94.44%	3 Missing ⚠️
src/fastcs/transports/epics/gui.py	57.14%	3 Missing ⚠️
src/fastcs/attributes/attr_w.py	95.00%	2 Missing ⚠️
src/fastcs/datatypes/datatype.py	92.30%	2 Missing ⚠️
src/fastcs/datatypes/table.py	94.73%	1 Missing ⚠️
src/fastcs/methods/scan.py	97.61%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #275      +/-   ##
==========================================
+ Coverage   89.38%   90.37%   +0.98%     
==========================================
  Files          46       68      +22     
  Lines        2280     2368      +88     
==========================================
+ Hits         2038     2140     +102     
+ Misses        242      228      -14     

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[shihab-dls]

Super nice! No notes, approving