chore: fix release workflow

[rickeylev]

My original change to use the bazel-contrib BCR publishing workflow was horribly broken.
This fixes a variety of issues.

• Fix the workflow call secrets variable name
• Allow getting the BCR publishing token from the workflow arg (the release
  workflow calls it)
• Fix the overall syntax of the workflows. It was just entirely invalid in
  several regards.
• Fix the yaml -> yml file name reference. NGL, it took me longer than I'd
  like to admit to see that, eh.

Along the way, some cleanups and improvements

• Allow specifying a particular tag to release, while using workflow state from
  a different commit. This allows us to make fixes on main, and then use it to
  manually re-trigger a tag to be released.
• Add descriptions for workflow inputs
• Allow bcr token to be passed to release. This will allow e.g. automatically
  scheduled releases.
• Quote shell variables because its good practice.

[gemini-code-assist]

Note

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