fix: route MongoDB PBM dataprotection through syncer

[gnolong]

Summary

This draft wires MongoDB PBM physical backup, physical restore, and PITR addon flows through the syncer dataprotection API for both sharding and replicaset topologies.

Changes include:

• run config-server, shard, and replicaset PBM sidecars under syncer with the pbm-agent workload type, while keeping PBM agent MongoDB connections local to each pod
• run mongos under syncer with the mongos workload type so it can participate in sharded restore coordination
• copy syncerctl into the data volume so ActionSet jobs can call the target pod syncer service remotely
• replace sharded and replicaset PBM physical backup/restore and PITR scripts with syncerctl backup, syncerctl restore, and syncerctl pitr calls
• persist PBM restore storage configuration into the syncer restore coordinator ConfigMap
• remove the old shard and replicaset restore-signal startup paths from PBM restore ActionSets
• keep fallback metadata handling for existing backups that do not yet include replset mapping extras

Local Validation

• bash -n for updated MongoDB dataprotection scripts
• git diff --check
• helm lint addons/mongodb
• helm template kb-addon-mongodb addons/mongodb --namespace kb-system
• SYNCER_TEST_TOPOLOGY=sharding SYNCER_TEST_RUN_E2E=true go test ./test/e2e/mongodb -run TestShardingFullBackupRestore -count=1 -v -timeout 45m
• SYNCER_TEST_TOPOLOGY=sharding SYNCER_TEST_RUN_E2E=true go test ./test/e2e/mongodb -run TestShardingPITR -count=1 -v -timeout 45m
• SYNCER_TEST_TOPOLOGY=replicaset SYNCER_TEST_RUN_E2E=true go test ./test/e2e/mongodb -run TestReplicaSetFullBackupRestore -count=1 -v -timeout 45m
• SYNCER_TEST_TOPOLOGY=replicaset SYNCER_TEST_RUN_E2E=true go test ./test/e2e/mongodb -run TestReplicaSetPITR -count=1 -v -timeout 45m

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (36eb2a3) to head (fe1414c).
⚠️ Report is 1 commits behind head on release-1.1.

Additional details and impacted files

@@             Coverage Diff             @@
##           release-1.1   #3110   +/-   ##
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  Coverage         0.00%   0.00%           
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  Files               73      73           
  Lines             9383    9383           
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  Misses            9383    9383           

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