feat: add generic /v1/completions client and token debug visualization

Add a generic FireworksV1CompletionsClient that handles local tokenization
via HuggingFace transformers and calls the /v1/completions endpoint with
token-in/token-out. Tool-call parsing is pluggable via a callback rather
than hardcoded to any specific domain.

Also add TokenDebugView component for the evaluation dashboard with:
- Text view: readable colored text with mask overlay (prompt vs completion)
- Episode view: per-token visualization with mask or logprob coloring
- Turns view: per-turn breakdown of prompt/completion tokens
- Token ID chips with hover tooltips showing detokenized text and logprob
- Smooth gradient logprob coloring (green=high confidence, red=low)

Made-with: Cursor

Author: benjibc

eval_protocol/integrations/__init__.py

@@ -3,5 +3,17 @@
 from .openeval import adapt
 from .trl import create_trl_adapter
 from .openai_rft import build_python_grader_from_evaluation_test
+from .fireworks_v1_completions_client import (
+    FireworksV1CompletionsClient,
+    ParsedToolCall,
+    to_openai_tool_calls,
+)
 
-__all__ = ["adapt", "create_trl_adapter", "build_python_grader_from_evaluation_test"]
+__all__ = [
+    "adapt",
+    "create_trl_adapter",
+    "build_python_grader_from_evaluation_test",
+    "FireworksV1CompletionsClient",
+    "ParsedToolCall",
+    "to_openai_tool_calls",
+]