Rename platform_llm_id to platform_model_id in LLMTokenCostReport for consistency

All other report types (ImgGen, Extract, Search, Fetch) already use
platform_model_id as the field name. The LLM report was the only one
using a domain-specific field name, while the serialized enum keys
remain domain-specific for flat dictionary output.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: lchoquel

pipelex/cogt/llm/llm_report.py

@@ -35,7 +35,7 @@ class LLMTokenCostReport(BaseModel):
     model_type: str = "llm"
     job_metadata: JobMetadata
     inference_model_name: str
-    platform_llm_id: str
+    platform_model_id: str
 
     nb_tokens_by_category: NbTokensByCategoryDict
     costs_by_token_category: CostsByCategoryDict
@@ -47,7 +47,7 @@ def as_flat_dictionary(self) -> dict[str, Any]:
         dict_for_llm: dict[str, Any] = {
             LLMTokenCostReportField.MODEL_TYPE: self.model_type,
             LLMTokenCostReportField.LLM_NAME: self.inference_model_name,
-            LLMTokenCostReportField.PLATFORM_LLM_ID: self.platform_llm_id,
+            LLMTokenCostReportField.PLATFORM_LLM_ID: self.platform_model_id,
         }
         the_dict.update(dict_for_llm)
         dict_for_nb_tokens = {

pipelex/cogt/usage/cost_registry.py

@@ -222,7 +222,7 @@ def compute_cost_report(cls, tokens_usage: TokensUsage) -> TokenCostReport:
                 model_type=tokens_usage.model_type,
                 job_metadata=tokens_usage.job_metadata,
                 inference_model_name=tokens_usage.inference_model_name,
-                platform_llm_id=tokens_usage.inference_model_id,
+                platform_model_id=tokens_usage.inference_model_id,
                 nb_tokens_by_category=tokens_usage.nb_tokens_by_category,
                 costs_by_token_category=costs_by_token_category,
             )