refactor(trace): decouple recorder from file persistence

Turn TraceRecorder into a lightweight trace event entry point and move
file persistence responsibilities into the default FileTraceSink. Trace
events are now published through TraceSinkRegistry, allowing additional
runtime observers to subscribe without parsing trace files.

Add TraceSink and TraceSinkRegistry, keep FileTraceSink registered as the
default sink, and preserve the existing active/historical/archived trace
file rotation behavior inside the file sink.

Also change TraceEvent to carry a logical key instead of a caller-provided
path, so trace storage locations are resolved internally under the traceroot. Update existing trace producers to emit logical keys such ascontext-workspace, exception, and advice targets.

Partner-Core/src/main/java/work/slhaf/partner/core/cognition/ContextWorkspace.kt

@@ -4,10 +4,8 @@ import com.alibaba.fastjson2.JSONObject
 import org.w3c.dom.Document
 import org.w3c.dom.Element
 import work.slhaf.partner.common.base.Block
-import work.slhaf.partner.framework.agent.config.ConfigCenter
 import work.slhaf.partner.framework.agent.log.TraceEvent
 import work.slhaf.partner.framework.agent.log.TraceRecorder
-import java.nio.file.Path
 import java.time.Duration
 import java.time.Instant
 import java.util.*
@@ -18,11 +16,6 @@ import kotlin.math.min
 
 class ContextWorkspace {
 
-    private val tracePath: Path = ConfigCenter.paths.stateDir
-        .resolve("trace")
-        .resolve("context-workspace")
-        .normalize()
-        .toAbsolutePath()
     private val stateSet = mutableSetOf<ContextBlock>()
     private val lock = ReentrantReadWriteLock()
 
@@ -157,7 +150,7 @@ class ContextWorkspace {
                     .thenBy { it.sourceKey.source }
             )
             .map(::blockSnapshot)
-        TraceRecorder.record(TraceEvent(tracePath, payload))
+        TraceRecorder.record(TraceEvent("context-workspace", payload))
     }
 
     private fun blockSnapshot(block: ContextBlock): JSONObject {