feat: channel field is added to the product_view table

feat: A new message `MarketingMethod` is added
fix!: `destination` field in the `product_performance_view` table is renamed to `marketing_method`
fix!: `destination` term in the `product_view` table is renamed to `reporting_context`
fix!: `predicted_gross_profit_change_fraction` and `predicted_monthly_gross_profit_change` fields are removed from the `price_insights_product_view` table
fix!: `ReportGranularity`, `RelativeDemand`, `RelativeDemandChangeType`, `TrafficSource` enums are wrapped into messages

PiperOrigin-RevId: 573186882

Source-Link: googleapis/googleapis@c88b603

Source-Link: googleapis/googleapis-gen@6ec73a6
Copy-Tag: eyJwIjoiamF2YS1zaG9wcGluZy1tZXJjaGFudC1yZXBvcnRzLy5Pd2xCb3QueWFtbCIsImgiOiI2ZWM3M2E2NGVkNWFkN2QxZGM3NDY2MDQ3Mjc5ZWU3ZmRkMGVmY2QxIn0=

feat: Channel enum is added

PiperOrigin-RevId: 572916805

Source-Link: googleapis/googleapis@3a90bf9

Source-Link: googleapis/googleapis-gen@23226f7
Copy-Tag: eyJwIjoiamF2YS1zaG9wcGluZy1tZXJjaGFudC1yZXBvcnRzLy5Pd2xCb3QueWFtbCIsImgiOiIyMzIyNmY3NjgwMDYxYTkxNDI0OTJjNzkxZDEzNzIyNWVjZmM0NTE1In0=

feat: ReportingContext enum is added
fix!: Destination enum is wrapped in a message

PiperOrigin-RevId: 572913446

Source-Link: googleapis/googleapis@28d3bc7

Source-Link: googleapis/googleapis-gen@38ead60
Copy-Tag: eyJwIjoiamF2YS1zaG9wcGluZy1tZXJjaGFudC1yZXBvcnRzLy5Pd2xCb3QueWFtbCIsImgiOiIzOGVhZDYwZmRhYzAzOWNhMDM2ZDhkZDhiZDZlY2E0MzA1NTE1ZDA1In0=

fix!: Update go_package and Go importpath:
  A new packaging option `cloud.google.com/go/shopping/css/apiv1/csspb;csspb` for `go_package` is added.
  An existing packaging option `google.golang.org/genproto/googleapis/shopping/css/v1;css` for `go_package` is removed.
  A new packaging option `cloud.google.com/go/shopping/merchant/inventories/apiv1beta/inventoriespb;inventoriespb` for `go_package` is added.
  An existing packaging option `google.golang.org/genproto/googleapis/shopping/merchant/inventories/v1beta;inventories` for `go_package` is removed.
  A new packaging option `cloud.google.com/go/shopping/type/typepb;typepb` for `go_package` is added.
  An existing packaging option `google.golang.org/genproto/googleapis/shopping/type/types;types` for `go_package` is removed.
  A new packaging option `cloud.google.com/go/shopping/type/typepb;typepb` for `go_package` is added.
  An existing packaging option `google.golang.org/genproto/googleapis/shopping/type/types;types` for `go_package` is removed.
  A new packaging option `cloud.google.com/go/shopping/merchant/reports/apiv1beta/reportspb;reportspb` for `go_package` is added.
  An existing packaging option `google.golang.org/genproto/googleapis/shopping/merchant/reports/v1beta;reports` for `go_package` is removed.

PiperOrigin-RevId: 572390800

Source-Link: googleapis/googleapis@b64fd17

Source-Link: googleapis/googleapis-gen@27ee81a
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