feat: add type hints to all public functions in trustgraph/base (#803)

feat: add type hints to all public functions in trustgraph/base

Add type annotations to 23 modules covering:
- Metrics classes (ConsumerMetrics, ProducerMetrics, etc.)
- Spec classes (ConsumerSpec, ProducerSpec, SubscriberSpec, etc.)
- Service classes with add_args() and run() methods
- Utility functions (logging, pubsub, clients)
- AsyncProcessor methods

All 93 public functions now fully typed.

Refs #785

* refactor: deduplicate imports and move __future__ after docstrings

Addresses review feedback on PR #803:
- Remove duplicate 'from argparse import ArgumentParser' across 12 files
- Move 'from __future__ import annotations' to line 1 in all files
- Clean up excessive blank lines

trustgraph-base/trustgraph/base/subscriber_spec.py

@@ -1,3 +1,6 @@
+from __future__ import annotations
+
+from typing import Any
 
 from . metrics import SubscriberMetrics
 from . subscriber import Subscriber
@@ -5,11 +8,11 @@ from . spec import Spec
 
 class SubscriberSpec(Spec):
 
-    def __init__(self, name, schema):
+    def __init__(self, name: str, schema: Any) -> None:
         self.name = name
         self.schema = schema
 
-    def add(self, flow, processor, definition):
+    def add(self, flow: Any, processor: Any, definition: dict[str, Any]) -> None:
 
         subscriber_metrics = SubscriberMetrics(
             processor = flow.id, flow = flow.name, name = self.name
@@ -27,4 +30,3 @@ class SubscriberSpec(Spec):
         # Put it in the consumer map, does that work?
         # It means it gets start/stop call.
         flow.consumer[self.name] = subscriber
-