feat: add MQTT, NATS, Redis Pub/Sub, and tRPC protocol linkers (Session 6)

Complete all 14 cross-service protocol linkers. Implements topic/subject
wildcard matching (MQTT +/#, NATS */>, Redis glob), tRPC procedure path
matching, and 31 new tests. Deletes servicelink_stubs.c — zero stubs remain.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: claude

Makefile.cbm

@@ -200,7 +200,11 @@ PIPELINE_SRCS = \
     src/pipeline/servicelink_sse.c \
     src/pipeline/servicelink_pubsub.c \
     src/pipeline/servicelink_rabbitmq.c \
-    src/pipeline/servicelink_eventbridge.c
+    src/pipeline/servicelink_eventbridge.c \
+    src/pipeline/servicelink_mqtt.c \
+    src/pipeline/servicelink_nats.c \
+    src/pipeline/servicelink_redis_pubsub.c \
+    src/pipeline/servicelink_trpc.c
 
 # SimHash / MinHash module
 SIMHASH_SRCS = src/simhash/minhash.c
@@ -337,6 +341,14 @@ TEST_SERVICELINK_RABBITMQ_SRCS = tests/test_servicelink_rabbitmq.c
 
 TEST_SERVICELINK_EVENTBRIDGE_SRCS = tests/test_servicelink_eventbridge.c
 
+TEST_SERVICELINK_MQTT_SRCS = tests/test_servicelink_mqtt.c
+
+TEST_SERVICELINK_NATS_SRCS = tests/test_servicelink_nats.c
+
+TEST_SERVICELINK_REDIS_PUBSUB_SRCS = tests/test_servicelink_redis_pubsub.c
+
+TEST_SERVICELINK_TRPC_SRCS = tests/test_servicelink_trpc.c
+
 TEST_CLI_SRCS = tests/test_cli.c
 
 TEST_MEM_SRCS = tests/test_mem.c
@@ -359,8 +371,12 @@ TEST_SERVICELINK_SSE_SRCS = tests/test_servicelink_sse.c
 TEST_SERVICELINK_PUBSUB_SRCS = tests/test_servicelink_pubsub.c
 TEST_SERVICELINK_RABBITMQ_SRCS = tests/test_servicelink_rabbitmq.c
 TEST_SERVICELINK_EVENTBRIDGE_SRCS = tests/test_servicelink_eventbridge.c
+TEST_SERVICELINK_MQTT_SRCS = tests/test_servicelink_mqtt.c
+TEST_SERVICELINK_NATS_SRCS = tests/test_servicelink_nats.c
+TEST_SERVICELINK_REDIS_PUBSUB_SRCS = tests/test_servicelink_redis_pubsub.c
+TEST_SERVICELINK_TRPC_SRCS = tests/test_servicelink_trpc.c
 
-ALL_TEST_SRCS = $(TEST_FOUNDATION_SRCS) $(TEST_EXTRACTION_SRCS) $(TEST_STORE_SRCS) $(TEST_CYPHER_SRCS) $(TEST_MCP_SRCS) $(TEST_DISCOVER_SRCS) $(TEST_GRAPH_BUFFER_SRCS) $(TEST_PIPELINE_SRCS) $(TEST_WATCHER_SRCS) $(TEST_LZ4_SRCS) $(TEST_SQLITE_WRITER_SRCS) $(TEST_GO_LSP_SRCS) $(TEST_C_LSP_SRCS) $(TEST_TRACES_SRCS) $(TEST_CLI_SRCS) $(TEST_MEM_SRCS) $(TEST_UI_SRCS) $(TEST_SECURITY_SRCS) $(TEST_YAML_SRCS) $(TEST_SIMHASH_SRCS) $(TEST_INTEGRATION_SRCS) $(TEST_SERVICELINK_GRAPHQL_SRCS) $(TEST_SERVICELINK_GRPC_SRCS) $(TEST_SERVICELINK_KAFKA_SRCS) $(TEST_SERVICELINK_SQS_SRCS) $(TEST_SERVICELINK_SNS_SRCS) $(TEST_SERVICELINK_WS_SRCS) $(TEST_SERVICELINK_SSE_SRCS) $(TEST_SERVICELINK_PUBSUB_SRCS) $(TEST_SERVICELINK_RABBITMQ_SRCS) $(TEST_SERVICELINK_EVENTBRIDGE_SRCS)
+ALL_TEST_SRCS = $(TEST_FOUNDATION_SRCS) $(TEST_EXTRACTION_SRCS) $(TEST_STORE_SRCS) $(TEST_CYPHER_SRCS) $(TEST_MCP_SRCS) $(TEST_DISCOVER_SRCS) $(TEST_GRAPH_BUFFER_SRCS) $(TEST_PIPELINE_SRCS) $(TEST_WATCHER_SRCS) $(TEST_LZ4_SRCS) $(TEST_SQLITE_WRITER_SRCS) $(TEST_GO_LSP_SRCS) $(TEST_C_LSP_SRCS) $(TEST_TRACES_SRCS) $(TEST_CLI_SRCS) $(TEST_MEM_SRCS) $(TEST_UI_SRCS) $(TEST_SECURITY_SRCS) $(TEST_YAML_SRCS) $(TEST_SIMHASH_SRCS) $(TEST_INTEGRATION_SRCS) $(TEST_SERVICELINK_GRAPHQL_SRCS) $(TEST_SERVICELINK_GRPC_SRCS) $(TEST_SERVICELINK_KAFKA_SRCS) $(TEST_SERVICELINK_SQS_SRCS) $(TEST_SERVICELINK_SNS_SRCS) $(TEST_SERVICELINK_WS_SRCS) $(TEST_SERVICELINK_SSE_SRCS) $(TEST_SERVICELINK_PUBSUB_SRCS) $(TEST_SERVICELINK_RABBITMQ_SRCS) $(TEST_SERVICELINK_EVENTBRIDGE_SRCS) $(TEST_SERVICELINK_MQTT_SRCS) $(TEST_SERVICELINK_NATS_SRCS) $(TEST_SERVICELINK_REDIS_PUBSUB_SRCS) $(TEST_SERVICELINK_TRPC_SRCS)
 
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