* Fixed metadata extraction on Windows by correctly splitting file paths
* `TestExtractFileMetadata`: Refactor a bit.
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Co-authored-by: Manu NALEPA <enalepa@offchainlabs.com>
* `reconstructSaveBroadcastDataColumnSidecars`: Use the `s.columnIndicesToSample` instead of recoding its content.
ddd
* Rename `custodyColumns` ==> `columnIndicesToSample`.
* `DataColumnStorage.Save`: Remove wrong godoc.
* Implement `receiveDataColumnSidecars` and transform `receiveDataColumnSidecar` as a subcase of the plural version.
* `dataColumnSubscriber`: Add godoc and remove only once used variable.
* `processDataColumnSidecarsFromExecution`: Use single flight directly in the function.
So the caller does not have any more the responsability to deal with multiple simultaneous calls.
* `processDataColumnSidecarsFromReconstruction`: Guard against a single flight.
In `dataColumnSubscriber`, trig in parallel `processDataColumnSidecarsFromReconstruction` and `processDataColumnSidecarsFromExecution`.
Stop when the first of them is successful.
* `processDataColumnSidecarsFromExecution`: Use `receiveDataColumnSidecars` instead of `receiveDataColumnSidecar`.
* Implement and use `broadcastAndReceiveUnseenDataColumnSidecars`.
* Add changelog.
* Fix James' comment.
* Fix James' comment.
* `processDataColumnSidecarsFromReconstruction`: Log reconstruction duration.
