docs(core): define standalone NUT-29 batch minting

[Egge21M]

Summary

• define a standalone Batch Mint Operation and ordered Batch Mint Members in the domain glossary
• record the additive API, persistence, reservation, history, event, and payment-method boundaries
• record exact-request write-ahead submission, atomic finalization, and whole-batch recovery decisions
• remove FEATURE_TODO.md so GitHub tickets remain the implementation plan

Impact

This is a documentation-only slice. It does not change runtime behavior, storage schemas, or the existing Mint Operation model. It establishes the contract for follow-up issues #422 through #427.

Validation

• bunx prettier@3.8.1 CONTEXT.md docs/adr/0009-model-batch-minting-as-a-standalone-operation.md docs/adr/0010-persist-exact-batch-issuance-before-submission.md --check
• git diff --check origin/master...HEAD
• verified that packages/ has no changes

Closes #421.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 0b6c6f3

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR