feat(daemon): add auto_pull config parameter for periodic remote sync

Add --auto-pull flag to control whether the daemon periodically pulls from
remote to check for updates from other clones.

Configuration precedence:
1. --auto-pull CLI flag (highest)
2. BEADS_AUTO_PULL environment variable
3. daemon.auto_pull in database config
4. Default: true when sync.branch is configured

When auto_pull is enabled, the daemon creates a remoteSyncTicker that
periodically calls doAutoImport() to pull remote changes. When disabled,
users must manually run 'git pull' to sync remote changes.

Changes:
- cmd/bd/daemon.go: Add --auto-pull flag and config reading logic
- cmd/bd/daemon_event_loop.go: Gate remoteSyncTicker on autoPull parameter
- cmd/bd/daemon_lifecycle.go: Add auto-pull to status output and spawn args
- internal/rpc/protocol.go: Add AutoPull field to StatusResponse
- internal/rpc/server_core.go: Add autoPull to Server struct and SetConfig
- internal/rpc/server_routing_validation_diagnostics.go: Include in status
- Tests updated to pass autoPull parameter

Closes #TBD

cmd/bd/daemon_integration_test.go

@@ -586,7 +586,7 @@ func TestEventDrivenLoop_PeriodicRemoteSync(t *testing.T) {
 
 	done := make(chan struct{})
 	go func() {
-		runEventDrivenLoop(ctx2, cancel2, server, serverErrChan, testStore, jsonlPath, doExport, doAutoImport, 0, log)
+		runEventDrivenLoop(ctx2, cancel2, server, serverErrChan, testStore, jsonlPath, doExport, doAutoImport, true, 0, log)
 		close(done)
 	}()