* fix(cost_calculator.py): handle custom pricing at deployment level for router
* test: add unit tests
* fix(router.py): show custom pricing on UI
check correct model str
* fix: fix linting error
* docs(custom_pricing.md): clarify custom pricing for proxy
Fixes https://github.com/BerriAI/litellm/issues/8573#issuecomment-2790420740
* test: update code qa test
* fix: cleanup traceback
* fix: handle litellm param custom pricing
* test: update test
* fix(cost_calculator.py): add router model id to list of potential model names
* fix(cost_calculator.py): fix router model id check
* fix: router.py - maintain older model registry approach
* fix: fix ruff check
* fix(router.py): router get deployment info
add custom values to mapped dict
* test: update test
* fix(utils.py): update only if value is non-null
* test: add unit test
* refactor(router.py): move assistants api endpoints to using 1 pass-through factory function
Reduces code, increases testing coverage
* refactor(router.py): reduce _common_check_available_deployment function size
make code more maintainable - reduce possible errors
* test(router_code_coverage.py): include batch_utils + pattern matching in enforced 100% code coverage
Improves reliability
* fix(router.py): fix model id match model dump
