Programmatic ORM mapper definitions

[skearnes]

• Hard-coded ORM mapper classes are replaced with generated classes based on the protocol buffer schema. This means that new message types and other changes will automatically be included in the mappers.
• Joined table inheritance for messages that appear in multiple contexts is replaced with single table inheritance for all message types (regardless of the number of contexts). This dramatically simplifies the schema---many fewer tables, more obvious cascading behavior, etc.---at the expense of losing the ability to enforce some uniqueness constraints (see the docstring for the mappers module). These constraints are still enforced on the protocol buffer side, which is the recommended entry point for creating new data.
• Some updates are made to the protocol buffer schema (I think these changes will be transparent to the binary protos in ord-data):
  • All message names are globally unique to avoid table name conflicts in the ORM (e.g. TemperatureConditions.Measurement -> TemperatureConditions.TemperatureMeasurement).
  • Source.id -> Source.catalog_id.
  • Some enum type names are also updated to be more explicit (Compound.IdentifierType -> Compound.CompoundIdentifierType).

[codecov[bot]]

Codecov Report

Merging #656 (6f06025) into main (8127d82) will decrease coverage by 5.46%. The diff coverage is 96.42%.

@@            Coverage Diff             @@
##             main     #656      +/-   ##
==========================================
- Coverage   74.51%   69.05%   -5.47%     
==========================================
  Files          23       23              
  Lines        2723     2236     -487     
  Branches      540      565      +25     
==========================================
- Hits         2029     1544     -485     
- Misses        584      585       +1     
+ Partials      110      107       -3     

Impacted Files	Coverage Δ
ord_schema/__init__.py	100.00% <ø> (ø)
ord_schema/message_helpers.py	86.51% <ø> (+0.65%)	:arrow_up:
ord_schema/orm/mappers.py	95.36% <95.83%> (-3.82%)	:arrow_down:
ord_schema/logging.py	100.00% <100.00%> (ø)
ord_schema/orm/__init__.py	100.00% <100.00%> (+5.00%)	:arrow_up:
ord_schema/orm/conftest.py	95.83% <100.00%> (ø)
ord_schema/orm/database.py	90.56% <100.00%> (ø)
ord_schema/orm/structure.py	91.46% <100.00%> (+0.21%)	:arrow_up:
ord_schema/validations.py	70.67% <100.00%> (ø)