refactor(reorg): extract endpoint + tool_type/tool_config/tool_product modules [7/10]

[valentijnscholten]

Stacked PRs

This is one of a stacked series that reorganizes dojo/ into self-contained dojo/{module}/ packages (matching the dojo/url/ reference). They are stacked — each PR is based on the previous one — so review and merge bottom-up in this order:

1. refactor(product_type): Extra ProductType models into dojo/product_type/ module [1/10] #14970 — product_type
2. refactor(test): Extract Test models into dojo/test/ module [2/10] #14971 — test
3. refactor(engagement): Extract Test models into dojo/test/ module [3/10] #14972 — engagement
4. refactor(product): Extract Product module into dojo/product/ [4/10] #14973 — product
5. refactor(finding): Reorganize finding into self-contained dojo/finding/ package [5/10] #14974 — finding (+ CWE & BurpRawRequestResponse fold-in)
6. refactor(reorg): extract user + system_settings modules [6/10] #14981 — peripheral: user + system_settings
7. refactor(reorg): extract endpoint + tool_type/tool_config/tool_product modules [7/10] #14982 — peripheral: endpoint + tool_type/tool_config/tool_product ◀ this PR
8. refactor(reorg): extract survey + benchmark modules [8/10] #14983 — peripheral: survey + benchmark
9. refactor(reorg): extract notes/note_type/file_uploads/reports/risk_acceptance [9/10] #14986 — peripheral: notes/note_type + file_uploads + reports + risk_acceptance
10. refactor(reorg): extract regulations/banner/announcement/development_environment/object [10/10] #14987 — peripheral: regulations + banner + announcement + development_environment + object

Merge #14970 first; each following branch is rebased onto the updated base and merged in turn. This PR continues the stack on top of #14981 — full implementation brief is the Phase 10 section in AGENTS.md.

Summary

Reorganizes the endpoint, tool_type, tool_config, and tool_product domains into self-contained dojo/{module}/ packages with ui/ and api/ sub-packages, matching the dojo/url/ reference layout. Pure code-movement: no behaviour or migration changes; backward-compat re-exports keep external consumers working.

endpoint (dojo/endpoint/)

• Move Endpoint_Params, Endpoint_Status, Endpoint into dojo/endpoint/{models,admin}.py. All FKs use string references; the dojo.models re-export keeps Endpoint resolvable for the remaining FKs that target it.
• Move the endpoint forms into ui/forms.py and the endpoint UI filters (EndpointFilterHelper, EndpointFilter, EndpointFilterWithoutObjectLookups) into ui/filters.py; the dojo/filters.py re-exports are dropped (they cycle with DojoFilter) and consumers in search/reports repoint to the new path. EndpointReportFilter is report-domain and stays in dojo/filters.py. ApiEndpointFilter moves to api/filters.py.
• Move the endpoint DRF serializers into api/serializer.py. EndpointSerializer.tags (a TagListSerializerField, which stays in api_v2/serializers.py) is resolved lazily in a get_fields() override so the module carries no top-level api_v2.serializers import. The moved ModelSerializers are re-exported from api_v2/serializers.py for prefetcher discovery and because ReportGenerateSerializer nests EndpointSerializer.
• Move EndPointViewSet, EndpointStatusViewSet, EndpointMetaImporterView into api/views.py and add dojo/endpoint/api/urls.py. The dojo/urls.py registration preserves the exact routes/basenames and the V3_FEATURE_LOCATIONS conditional: endpoint_meta_import is always registered; under V3 the location-compat viewsets serve endpoints/endpoint_status, otherwise add_endpoint_urls registers the legacy viewsets.
• Move views.py/urls.py into ui/; queries.py/signals.py/utils.py stay.

tool_type / tool_config / tool_product

• Move Tool_Type, Tool_Configuration, Tool_Product_Settings, Tool_Product_History into their {models,admin}.py (string-ref FKs). The ToolConfigForm_Admin (ModelForm) and Tool_Configuration_Admin (ModelAdmin) helpers move from dojo/models.py into dojo/tool_config/admin.py.
• Move the tool forms into each module's ui/forms.py, the serializers into api/serializer.py (re-exported for prefetcher discovery), and ToolConfigurationsViewSet/ToolProductSettingsViewSet/ToolTypesViewSet into api/views.py with add_*_urls, preserving routes/basenames.
• Move each module's views.py/urls.py into ui/; tool_config/factory.py and tool_product/queries.py/signals.py stay.