fix(types): use is_given at call sites pyright flagged

Replace direct identity checks against NOT_GIVEN with is_given() at
sites where pyright's inability to narrow on non-singleton sentinels
was causing type errors.

- adapters/services/anthropic_adapter.py: narrow converted.system for
  _resolve_system_instruction.
- services/openai/llm.py: narrow params.service_tier using OpenAI's
  is_given.
- services/sarvam/llm.py: narrow tools / tool_choice using OpenAI's
  is_given (aliased as openai_is_given alongside the existing
  settings.is_given import).
- services/sarvam/tts.py: narrow settings.voice using settings.is_given.

src/pipecat/adapters/services/anthropic_adapter.py

@@ -91,7 +91,7 @@ class AnthropicLLMAdapter(BaseLLMAdapter[AnthropicLLMInvocationParams]):
             self.get_messages(context), system_instruction=system_instruction
         )
         system = self._resolve_system_instruction(
-            converted.system if converted.system is not NOT_GIVEN else None,
+            converted.system if is_given(converted.system) else None,
             system_instruction,
             discard_context_system=True,
         )

src/pipecat/services/openai/llm.py

@@ -8,6 +8,7 @@
 
 from openai import NOT_GIVEN
 
+from pipecat.adapters.services.open_ai_adapter import is_given
 from pipecat.services.openai.base_llm import BaseOpenAILLMService
 
 
@@ -71,7 +72,7 @@ class OpenAILLMService(BaseOpenAILLMService):
             default_settings.model = model
 
         # Handle service_tier from deprecated params
-        if params is not None and not settings and params.service_tier is not NOT_GIVEN:
+        if params is not None and not settings and is_given(params.service_tier):
             service_tier = service_tier or params.service_tier
 
         # 3. Apply params overrides — only if settings not provided

src/pipecat/services/sarvam/llm.py

@@ -14,6 +14,7 @@ from loguru import logger
 from openai import NOT_GIVEN
 
 from pipecat.adapters.services.open_ai_adapter import OpenAILLMInvocationParams
+from pipecat.adapters.services.open_ai_adapter import is_given as openai_is_given
 from pipecat.services.openai.base_llm import OpenAILLMSettings
 from pipecat.services.openai.llm import OpenAILLMService
 from pipecat.services.sarvam._sdk import sdk_headers
@@ -158,11 +159,11 @@ class SarvamLLMService(OpenAILLMService):
         tool_choice = params_from_context.get("tool_choice", NOT_GIVEN)
 
         has_tools = (
-            tools is not NOT_GIVEN
+            openai_is_given(tools)
             and tools is not None
             and (not isinstance(tools, list) or len(tools) > 0)
         )
-        has_tool_choice = tool_choice is not NOT_GIVEN and tool_choice is not None
+        has_tool_choice = openai_is_given(tool_choice) and tool_choice is not None
 
         if has_tool_choice and not has_tools:
             raise ValueError("Sarvam requires non-empty `tools` when `tool_choice` is provided.")

src/pipecat/services/sarvam/tts.py

@@ -59,7 +59,7 @@ from pipecat.frames.frames import (
     TTSStoppedFrame,
 )
 from pipecat.services.sarvam._sdk import sdk_headers
-from pipecat.services.settings import NOT_GIVEN, TTSSettings, _NotGiven
+from pipecat.services.settings import NOT_GIVEN, TTSSettings, _NotGiven, is_given
 from pipecat.services.tts_service import InterruptibleTTSService, TextAggregationMode, TTSService
 from pipecat.transcriptions.language import Language, resolve_language
 from pipecat.utils.tracing.service_decorators import traced_tts
@@ -501,7 +501,7 @@ class SarvamHttpTTSService(TTSService):
             sample_rate = self._config.default_sample_rate
 
         # Set default voice based on model if not specified via any mechanism
-        if voice_id is None and (settings is None or settings.voice is NOT_GIVEN):
+        if voice_id is None and (settings is None or not is_given(settings.voice)):
             default_settings.voice = self._config.default_speaker
 
         # Validate and clamp pace to model's valid range
@@ -919,7 +919,7 @@ class SarvamTTSService(InterruptibleTTSService):
             sample_rate = self._config.default_sample_rate
 
         # Set default voice based on model if not specified via any mechanism
-        if voice_id is None and (settings is None or settings.voice is NOT_GIVEN):
+        if voice_id is None and (settings is None or not is_given(settings.voice)):
             default_settings.voice = self._config.default_speaker
 
         # Validate and clamp pace to model's valid range