refactor: copybara overhaul (#4771)

Make the transform simpler by removing special cases:

- moving the "help topics" docs under cli/core, give up on publishing
them on the public site for now.
- move one import to a separate block so it doesn't get re-ordered after
rewriting our go imports
- express the transforms as silo -> OSS which is the way we think about
it now. Originally when I wrote this, the direction was opposite since
we were bringing the OSS repo into silo.
- move the go_generated_sources helper

Added a couple more copybara workflows that let me test locally and iron
out the diffs.

---

### Type of change

- Refactor (a code change that neither fixes a bug or adds a new
feature)

### Test plan

- Manual testing; please provide instructions so we can reproduce:

Run a sync from this branch, it's totally clean with no manual fixups:
#651

Also ran the two added workflows and checked in meld that the transforms
line up in both directions.
Did not test the import_pr workflow yet, will do after this lands.

GitOrigin-RevId: bfb27b61d7c85691a776d1db852da03b5617ac36

pkg/aspect/lint/lint.go

@@ -1,19 +1,3 @@
-/*
- * Copyright 2023 Aspect Build Systems, Inc.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
 /*
  * Copyright 2022 Aspect Build Systems, Inc.
  *
@@ -129,7 +113,7 @@ lint:
 	output, _ := cmd.Flags().GetString("output")
 
 	bazelCmd := []string{"build"}
-	bazelCmd = append(bazelCmd, cmd.Flags().Args()...)
+	bazelCmd = append(bazelCmd, args...)
 	bazelCmd = append(bazelCmd, fmt.Sprintf("--aspects=%s", strings.Join(linters, ",")))
 
 	outputGroups := []string{}