Added scan_version feature flag to sharepoint proto

[MuneebUllahKhan222]

Description:

This PR introduces a scan_version, scan_comments, scan_attachments source configs flags for sharepoint source in soures.protos file.

Checklist:

• Tests passing (make test-community)?
• Lint passing (make lint this requires golangci-lint)?

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Note

Medium Risk
Adds a new bool field to the Sharepoint protobuf message, which changes the public proto/API surface and requires downstream regeneration/compatibility consideration, but does not alter runtime logic beyond message shape.

Overview
Adds a SharePoint feature flag to the API schema. The Sharepoint proto now includes a scan_versions boolean field, and the generated Go protobuf (sources.pb.go) and validation stubs (sources.pb.validate.go) are updated accordingly (including a new GetScanVersions() accessor).

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[gugacyber]

The poto changes look correct — field numbers 3, 4, 5 are fresh and don't conflict with existing fields, and the raw descriptor bytes in sources.pb.go are consistent with the new fields.
One thing worth noting: the three new flags default to false (protobuf bool default), meaning existing configs silently opt out of scanning versions, comments, and attachments after upgrading. If the previous behavior was to scan these by default, this is a silent breaking change for existing users. Worth documenting in the PR whether the old behavior scanned these or not, and if so, defaulting to true or adding a migration note.
Also, the PR description mentions scan_version (singular) but the field added is scan_versions (plural) — minor inconsistency in the description.