loadIndexesFromAuthoritativeShard and the router-level CmdListIndexes::typedRun share nearly identical routing logic (CollectionRoutingInfoTargeter setup, timeseries namespace rewriting, shard selection via minKey chunk, and command execution).

We should deduplicate by exposing a cluster::listIndexes() function, following the established pattern of cluster::createCollection() and the approach taken in SERVER-123175 for cluster::createIndexes().

Proposal

• Add a cluster::listIndexes() function (e.g. in cluster_ddl.h) that encapsulates the shared logic: building the ListIndexes command, handling timeseries namespace rewriting via CollectionRoutingInfoTargeter, selecting the shard owning the minKey chunk (or primary shard for unsharded collections), and executing the command.
• The new function should accept a parameter controlling whether to drain the full cursor internally (for internal callers like loadIndexesFromAuthoritativeShard) or return a passthrough cursor (for the client-facing command).
• Refactor CmdListIndexes::typedRun and loadIndexesFromAuthoritativeShard to both delegate to cluster::listIndexes().
• Current callers of loadIndexesFromAuthoritativeShard (shardsvr_process_interface, mongos_process_interface, rename_collection_coordinator) would switch to the new shared function.