re_protos: expose Tasks endpoints via the redap_frontend (#9578)

### Related

* Depends on: #9572
* Part of: rerun-io/dataplatform#545
* Proto definition for:
rerun-io/dataplatform#574

### What
Expose the Task Service endpoint via the frontend.

Signed-off-by: Andrea Reale <[email protected]>

Author: andrea-reale

buf.yaml

@@ -26,6 +26,7 @@ lint:
       - crates/store/re_protos/proto/rerun/v1alpha1/frontend.proto
       - crates/store/re_protos/proto/rerun/v1alpha1/manifest_registry.proto
       - crates/store/re_protos/proto/rerun/v1alpha1/catalog.proto
+      - crates/store/re_protos/proto/rerun/v1alpha1/tasks.proto
   enum_zero_value_suffix: _UNSPECIFIED # see <https://buf.build/docs/lint/rules/?h=enum_zero_value#enum_zero_value_suffix>
 breaking:
   use:

crates/store/re_protos/proto/rerun/v1alpha1/frontend.proto

@@ -5,6 +5,7 @@ package rerun.frontend.v1alpha1;
 import "rerun/v1alpha1/catalog.proto";
 import "rerun/v1alpha1/common.proto";
 import "rerun/v1alpha1/manifest_registry.proto";
+import "rerun/v1alpha1/tasks.proto";
 
 // TODO(cmc): I've decided to re-use the underlying response types for now, in the name of expediency.
 // This is bad in the long term (breaking changes to the internal APIs should not result in breaking
@@ -105,6 +106,16 @@ service FrontendService {
 
   rpc GetTableSchema(GetTableSchemaRequest) returns (GetTableSchemaResponse) {}
   rpc ScanTable(ScanTableRequest) returns (stream ScanTableResponse) {}
+
+  // --- Tasks service ---
+  // Query the status of submitted tasks
+  rpc Query(rerun.redap_tasks.v1alpha1.QueryRequest) returns (rerun.redap_tasks.v1alpha1.QueryResponse) {}
+
+  // Fetch the output of a completed task
+  rpc FetchOutput(rerun.redap_tasks.v1alpha1.FetchOutputRequest) returns (rerun.redap_tasks.v1alpha1.FetchOutputResponse) {}
+
+  // Query the status of submitted tasks as soon as they are no longer pending
+  rpc QueryOnCompletion(rerun.redap_tasks.v1alpha1.QueryOnCompletionRequest) returns (stream rerun.redap_tasks.v1alpha1.QueryOnCompletionResponse) {}
 }
 
 // --- Manifest Registry ---