ci: enable Renovate automerge and fix changeset workflow

[insipx]

What

• renovate.json: add automerge: true + platformAutomerge: true so enabled (@xmtp/**) dependency PRs merge automatically.
• renovate-changeset.yml: set use-conventional-commits: false.

Why

The changeset workflow was silently no-op'ing on every Renovate PR. Our commits are prefixed chore(deps):; the action's conventional-commit parser maps any non-fix/feat prefix to an update type of none and skips the PR without writing a changeset (runs went green but did nothing). With use-conventional-commits: false, the action defaults every dependency update to a patch changeset.

Automerge gating

Merge now requires the build CI check (added as a required status check on main) plus a review from Macroscope. Flow: Renovate opens PR → changeset workflow pushes a patch changeset → CI build passes → Macroscope approves → auto-merge.

🤖 Generated with Claude Code

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Note

Enable Renovate automerge and fix changeset workflow

• Enables native platform automerge in renovate.json by setting automerge and platformAutomerge to true.
• Disables conventional commit parsing in renovate-changeset.yml so dependency updates default to patch changesets instead of deriving the update type from commit messages.

^{Macroscope summarized 8323ae4.}

[macroscopeapp]

Approvability

Verdict: Approved

Minor CI/CD configuration changes that enable Renovate automerge and fix changeset generation for dependency updates. No runtime behavior impact - only affects the dependency update pipeline.

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