fix: pagination in stac api (#472)

### Issue

#473

### What? / Why?

- Pagination was not working due changes made to [Pagination extension
](https://stac-utils.github.io/stac-fastapi/migrations/v3.0.0/#request-models).
Updating to use a request model fixed it.
### Testing?


https://jtran.delta-backend.com/api/stac/collections/snow-projections-diff-245/items?token=next:snow-projections-diff-245:CSCD_SWE_tavg_ssp245_20770401_percChange.cog

Author: botanical

stac_api/runtime/src/app.py

@@ -8,6 +8,7 @@
 from src.config import TilesApiSettings, api_settings
 from src.config import extensions as PgStacExtensions
 from src.config import get_request_model as GETModel
+from src.config import items_get_request_model
 from src.config import post_request_model as POSTModel
 from src.extension import TiTilerExtension
 
@@ -74,6 +75,7 @@ async def lifespan(app: FastAPI):
     client=VedaCrudClient(post_request_model=POSTModel),
     search_get_request_model=GETModel,
     search_post_request_model=POSTModel,
+    items_get_request_model=items_get_request_model,
     response_class=ORJSONResponse,
     middlewares=[Middleware(CompressionMiddleware), Middleware(ValidationMiddleware)],
     router=APIRouter(route_class=LoggerRouteHandler),

stac_api/runtime/src/config.py

@@ -11,7 +11,12 @@
 from pydantic_settings import BaseSettings, SettingsConfigDict
 
 from fastapi.responses import ORJSONResponse
-from stac_fastapi.api.models import create_get_request_model, create_post_request_model
+from stac_fastapi.api.models import (
+    ItemCollectionUri,
+    create_get_request_model,
+    create_post_request_model,
+    create_request_model,
+)
 
 # from stac_fastapi.pgstac.extensions import QueryExtension
 from stac_fastapi.extensions.core import (
@@ -132,14 +137,22 @@ def TilesApiSettings() -> _TilesApiSettings:
     return _TilesApiSettings()
 
 
+pagination_extension = TokenPaginationExtension()
+
 extensions = [
     FieldsExtension(),
     FilterExtension(),
     QueryExtension(),
     SortExtension(),
-    TokenPaginationExtension(),
+    pagination_extension,
 ]
 
+items_get_request_model = create_request_model(
+    "ItemCollectionURI",
+    base_model=ItemCollectionUri,
+    mixins=[pagination_extension.GET],
+)
+
 if api_settings.enable_transactions:
     extensions.extend(
         [