Accumulated changes for message queue (#6600)

* rename

* set agent address

* refactor

* add agent sub

* pub messages

* grpc new client

* can publish records via agent

* send init message with session id

* fmt

* check cancelled request while waiting

* use sessionId

* handle possible nil stream

* subscriber process messages

* separate debug port

* use atomic int64

* less logs

* minor

* skip io.EOF

* rename

* remove unused

* use saved offsets

* do not reuse session, since always session id is new after restart

remove last active ts from SessionEntry

* simplify printing

* purge unused

* just proxy the subscription, skipping the session step

* adjust offset types

* subscribe offset type and possible value

* start after the known tsns

* avoid wrongly set startPosition

* move

* remove

* refactor

* typo

* fix

* fix changed path

weed/util/log_buffer/log_read.go

@@ -66,17 +66,10 @@ func (logBuffer *LogBuffer) LoopProcessLogData(readerName string, startPosition
 				isDone = true
 				return
 			}
-			logBuffer.RLock()
-			lastTsNs := logBuffer.LastTsNs
-			logBuffer.RUnlock()
-			loopTsNs := lastTsNs // make a copy
+			lastTsNs := logBuffer.LastTsNs.Load()
 
-			for lastTsNs == loopTsNs {
+			for lastTsNs == logBuffer.LastTsNs.Load() {
 				if waitForDataFn() {
-					// Update loopTsNs and loop again
-					logBuffer.RLock()
-					loopTsNs = logBuffer.LastTsNs
-					logBuffer.RUnlock()
 					continue
 				} else {
 					isDone = true