Admin UI: Fetch task logs (#7114)

* show task details

* loading tasks

* task UI works

* generic rendering

* rendering the export link

* removing placementConflicts from task parameters

* remove TaskSourceLocation

* remove "Server ID" column

* rendering balance task source

* sources and targets

* fix ec task generation

* move info

* render timeline

* simplified worker id

* simplify

* read task logs from worker

* isValidTaskID

* address comments

* Update weed/worker/tasks/balance/execution.go

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Update weed/worker/tasks/erasure_coding/ec_task.go

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Update weed/worker/tasks/task_log_handler.go

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* fix shard ids

* plan distributing shard id

* rendering planned shards in task details

* remove Conflicts

* worker logs correctly

* pass in dc and rack

* task logging

* Update weed/admin/maintenance/maintenance_queue.go

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

* display log details

* logs have fields now

* sort field keys

* fix link

* fix collection filtering

* avoid hard coded ec shard counts

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

weed/worker/log_adapter.go

@@ -0,0 +1,85 @@
+package worker
+
+import (
+	"fmt"
+
+	wtasks "github.com/seaweedfs/seaweedfs/weed/worker/tasks"
+	wtypes "github.com/seaweedfs/seaweedfs/weed/worker/types"
+)
+
+// taskLoggerAdapter adapts a tasks.TaskLogger to the types.Logger interface used by tasks
+// so that structured WithFields logs from task implementations are captured into file logs.
+type taskLoggerAdapter struct {
+	base   wtasks.TaskLogger
+	fields map[string]interface{}
+}
+
+func newTaskLoggerAdapter(base wtasks.TaskLogger) *taskLoggerAdapter {
+	return &taskLoggerAdapter{base: base}
+}
+
+// WithFields returns a new adapter instance that includes the provided fields.
+func (a *taskLoggerAdapter) WithFields(fields map[string]interface{}) wtypes.Logger {
+	// copy fields to avoid mutation by caller
+	copied := make(map[string]interface{}, len(fields))
+	for k, v := range fields {
+		copied[k] = v
+	}
+	return &taskLoggerAdapter{base: a.base, fields: copied}
+}
+
+// Info logs an info message, including any structured fields if present.
+func (a *taskLoggerAdapter) Info(msg string, args ...interface{}) {
+	if a.base == nil {
+		return
+	}
+	if len(a.fields) > 0 {
+		a.base.LogWithFields("INFO", fmt.Sprintf(msg, args...), toStringMap(a.fields))
+		return
+	}
+	a.base.Info(msg, args...)
+}
+
+func (a *taskLoggerAdapter) Warning(msg string, args ...interface{}) {
+	if a.base == nil {
+		return
+	}
+	if len(a.fields) > 0 {
+		a.base.LogWithFields("WARNING", fmt.Sprintf(msg, args...), toStringMap(a.fields))
+		return
+	}
+	a.base.Warning(msg, args...)
+}
+
+func (a *taskLoggerAdapter) Error(msg string, args ...interface{}) {
+	if a.base == nil {
+		return
+	}
+	if len(a.fields) > 0 {
+		a.base.LogWithFields("ERROR", fmt.Sprintf(msg, args...), toStringMap(a.fields))
+		return
+	}
+	a.base.Error(msg, args...)
+}
+
+func (a *taskLoggerAdapter) Debug(msg string, args ...interface{}) {
+	if a.base == nil {
+		return
+	}
+	if len(a.fields) > 0 {
+		a.base.LogWithFields("DEBUG", fmt.Sprintf(msg, args...), toStringMap(a.fields))
+		return
+	}
+	a.base.Debug(msg, args...)
+}
+
+// toStringMap converts map[string]interface{} to map[string]interface{} where values are printable.
+// The underlying tasks.TaskLogger handles arbitrary JSON values, but our gRPC conversion later
+// expects strings; we rely on existing conversion there. Here we keep interface{} to preserve detail.
+func toStringMap(in map[string]interface{}) map[string]interface{} {
+	out := make(map[string]interface{}, len(in))
+	for k, v := range in {
+		out[k] = v
+	}
+	return out
+}