[DOCS] PYDANTIC_GUIDE.md documents a package layout the repo no longer uses #604

PYDANTIC_GUIDE.md documents a package layout the repo no longer uses. Raised by Roel Bollens (@RoelBollens-TomTom) while reviewing #598 (#598 (comment)); filing separately because the staleness predates that PR and fixing it there would be out of scope.

Entry point example is wrong on both axes

Lines 850-856 show:

[project.entry-points."overture.models"]
"transportation.connector" = "overture.schema.transportation.connector.models:Connector"
"transportation.segment" = "overture.schema.transportation.segment.models:Segment"

Real declaration in packages/overture-schema-transportation-theme/pyproject.toml:

[project.entry-points."overture.models"]
connector = "overture.schema.transportation:Connector"
segment = "overture.schema.transportation:Segment"

Keys are unqualified, not theme-prefixed, and targets resolve off the theme package root rather than a <type>.models submodule.

The models.py / type-subdirectory convention is gone

Lines 1006-1018 prescribe a type subdirectory per feature type with models.py / enums.py / types.py inside it. overture-schema-buildings-theme already contradicts this -- flat building.py, building_part.py, _common.py directly under overture/schema/buildings/, no subdirectory and no models.py. #598 does the same for transportation (connector.py, and segment/{_common,road,rail,water}.py), which removes the last models.py in a theme package; the file name survives only in overture-schema-common and overture-schema-annex.

Dead path references

• L857 links packages/overture-schema-transportation-theme/src/overture/schema/transportation/segment/models.py -- resolves today, breaks when [REFACTOR] Organize transportation theme Pydantic package, add relationships, sync JSON Schema, and tidy docs #598 merges.
• L1098 comments # In overture-schema-buildings-theme/src/overture/schema/buildings/building/models.py -- already dead.
• L1139 comments # In buildings/models.py -- already dead.

Not stale

Every from overture.schema.* import in the guide resolves on main (11 distinct modules, all import cleanly), including the recent system.primitive split into system.numeric / system.geometric. The rot is confined to file layout and entry point naming, not the import surface.

Scope

Rewrite the "Module Organization" and entry point registration sections against the buildings / post-#598 transportation layout, and repoint the three path references. Best done after #598 lands so the transportation examples describe the settled structure.