Pub/sub abstraction: decouple from Pulsar (#751)

Remove Pulsar-specific concepts from application code so that
the pub/sub backend is swappable via configuration.

Rename translators:
- to_pulsar/from_pulsar → decode/encode across all translator
  classes, dispatch handlers, and tests (55+ files)
- from_response_with_completion → encode_with_completion
- Remove pulsar.schema.Record from translator base class

Queue naming (CLASS:TOPICSPACE:TOPIC):
- Replace topic() helper with queue() using new format:
  flow:tg:name, request:tg:name, response:tg:name, state:tg:name
- Queue class implies persistence/TTL (no QoS in names)
- Update Pulsar backend map_topic() to parse new format
- Librarian queues use flow class (persistent, for chunking)
- Config push uses state class (persistent, last-value)
- Remove 15 dead topic imports from schema files
- Update init_trustgraph.py namespace: config → state

Confine Pulsar to pulsar_backend.py:
- Delete legacy PulsarClient class from pubsub.py
- Move add_args to add_pubsub_args() with standalone flag
  for CLI tools (defaults to localhost)
- PulsarBackendConsumer.receive() catches _pulsar.Timeout,
  raises standard TimeoutError
- Remove Pulsar imports from: async_processor, flow_processor,
  log_level, all 11 client files, 4 storage writers, gateway
  service, gateway config receiver
- Remove log_level/LoggerLevel from client API
- Rewrite tg-monitor-prompts to use backend abstraction
- Update tg-dump-queues to use add_pubsub_args

Also: pubsub-abstraction.md tech spec covering problem statement,
design goals, as-is requirements, candidate broker assessment,
approach, and implementation order.

trustgraph-base/trustgraph/schema/services/agent.py

@@ -2,7 +2,6 @@
 from dataclasses import dataclass, field
 from typing import Optional
 
-from ..core.topic import topic
 from ..core.primitives import Error
 
 ############################################################################

trustgraph-base/trustgraph/schema/services/collection.py

@@ -2,7 +2,7 @@ from dataclasses import dataclass, field
 from datetime import datetime
 
 from ..core.primitives import Error
-from ..core.topic import topic
+from ..core.topic import queue
 
 ############################################################################
 
@@ -50,10 +50,6 @@ class CollectionManagementResponse:
 
 # Topics
 
-collection_request_queue = topic(
-    'collection', qos='q0', namespace='request'
-)
-collection_response_queue = topic(
-    'collection', qos='q0', namespace='response'
-)
+collection_request_queue = queue('collection', cls='request')
+collection_response_queue = queue('collection', cls='response')
 

trustgraph-base/trustgraph/schema/services/config.py

@@ -1,7 +1,7 @@
 
 from dataclasses import dataclass, field
 
-from ..core.topic import topic
+from ..core.topic import queue
 from ..core.primitives import Error
 
 ############################################################################
@@ -60,15 +60,9 @@ class ConfigPush:
     version: int = 0
     config: dict[str, dict[str, str]] = field(default_factory=dict)
 
-config_request_queue = topic(
-    'config', qos='q0', namespace='request'
-)
-config_response_queue = topic(
-    'config', qos='q0', namespace='response'
-)
-config_push_queue = topic(
-    'config', qos='q2', namespace='config'
-)
+config_request_queue = queue('config', cls='request')
+config_response_queue = queue('config', cls='response')
+config_push_queue = queue('config', cls='state')
 
 ############################################################################
 

trustgraph-base/trustgraph/schema/services/flow.py

@@ -1,7 +1,7 @@
 
 from dataclasses import dataclass, field
 
-from ..core.topic import topic
+from ..core.topic import queue
 from ..core.primitives import Error
 
 ############################################################################
@@ -61,12 +61,8 @@ class FlowResponse:
     # Everything
     error: Error | None = None
 
-flow_request_queue = topic(
-    'flow', qos='q0', namespace='request'
-)
-flow_response_queue = topic(
-    'flow', qos='q0', namespace='response'
-)
+flow_request_queue = queue('flow', cls='request')
+flow_response_queue = queue('flow', cls='response')
 
 ############################################################################
 

trustgraph-base/trustgraph/schema/services/library.py

@@ -1,6 +1,6 @@
 from dataclasses import dataclass, field
 from ..core.primitives import Triple, Error
-from ..core.topic import topic
+from ..core.topic import queue
 from ..core.metadata import Metadata
 # Note: Document imports will be updated after knowledge schemas are converted
 
@@ -220,9 +220,5 @@ class LibrarianResponse:
 # FIXME: Is this right?  Using persistence on librarian so that
 # message chunking works
 
-librarian_request_queue = topic(
-    'librarian', qos='q1', namespace='request'
-)
-librarian_response_queue = topic(
-    'librarian', qos='q1', namespace='response',
-)
+librarian_request_queue = queue('librarian-request', cls='flow')
+librarian_response_queue = queue('librarian-response', cls='flow')

trustgraph-base/trustgraph/schema/services/llm.py

@@ -1,7 +1,6 @@
 
 from dataclasses import dataclass, field
 
-from ..core.topic import topic
 from ..core.primitives import Error
 
 ############################################################################

trustgraph-base/trustgraph/schema/services/lookup.py

@@ -1,7 +1,6 @@
 from dataclasses import dataclass
 
 from ..core.primitives import Error, Term, Triple
-from ..core.topic import topic
 from ..core.metadata import Metadata
 
 ############################################################################

trustgraph-base/trustgraph/schema/services/nlp_query.py

@@ -1,7 +1,6 @@
 from dataclasses import dataclass, field
 
 from ..core.primitives import Error
-from ..core.topic import topic
 
 ############################################################################
 

trustgraph-base/trustgraph/schema/services/prompt.py

@@ -1,7 +1,6 @@
 from dataclasses import dataclass, field
 
 from ..core.primitives import Error
-from ..core.topic import topic
 
 ############################################################################
 

trustgraph-base/trustgraph/schema/services/query.py

@@ -1,7 +1,7 @@
 from dataclasses import dataclass, field
 
 from ..core.primitives import Error, Term, Triple
-from ..core.topic import topic
+from ..core.topic import queue
 
 ############################################################################
 
@@ -69,12 +69,8 @@ class DocumentEmbeddingsResponse:
     error: Error | None = None
     chunks: list[ChunkMatch] = field(default_factory=list)
 
-document_embeddings_request_queue = topic(
-    "document-embeddings-request", qos='q0', tenant='trustgraph', namespace='flow'
-)
-document_embeddings_response_queue = topic(
-    "document-embeddings-response", qos='q0', tenant='trustgraph', namespace='flow'
-)
+document_embeddings_request_queue = queue('document-embeddings', cls='request')
+document_embeddings_response_queue = queue('document-embeddings', cls='response')
 
 ############################################################################
 
@@ -104,9 +100,5 @@ class RowEmbeddingsResponse:
     error: Error | None = None
     matches: list[RowIndexMatch] = field(default_factory=list)
 
-row_embeddings_request_queue = topic(
-    "row-embeddings-request", qos='q0', tenant='trustgraph', namespace='flow'
-)
-row_embeddings_response_queue = topic(
-    "row-embeddings-response", qos='q0', tenant='trustgraph', namespace='flow'
-)
+row_embeddings_request_queue = queue('row-embeddings', cls='request')
+row_embeddings_response_queue = queue('row-embeddings', cls='response')

trustgraph-base/trustgraph/schema/services/retrieval.py

@@ -1,5 +1,4 @@
 from dataclasses import dataclass
-from ..core.topic import topic
 from ..core.primitives import Error, Term
 
 ############################################################################

trustgraph-base/trustgraph/schema/services/rows_query.py

@@ -2,7 +2,6 @@ from dataclasses import dataclass, field
 from typing import Optional
 
 from ..core.primitives import Error
-from ..core.topic import topic
 
 ############################################################################
 

trustgraph-base/trustgraph/schema/services/structured_query.py

@@ -1,7 +1,6 @@
 from dataclasses import dataclass, field
 
 from ..core.primitives import Error
-from ..core.topic import topic
 
 ############################################################################