Dry run changelog show documents created

[davidoort]

Currently setting dryRun: true shows a before and after (if there's changes) on the documents we are migrating over. Sometimes migrations create documents in other tables or update documents in other tables and it would be great to have a full trace of what has been updated.

[otterraphael]

This should be covered now: in we wrap and emit a best-effort write trace for inserts/patches/replaces/deletes (including secondary table writes), alongside the before/after examples for the primary table.\n\nSee README section ‘Test a migration with dryRun’ + implementation in around the log.

[otterraphael]

Follow-up w/ specifics (my prior comment ate backticks):

• Implementation: migrations/src/client/index.ts wraps ctx.db in dryRun and records insert/patch/replace/delete calls, then logs DRY RUN: Write trace (rolled back) with counts + examples.
• Docs: README.md “Test a migration with dryRun” calls this out explicitly.

Net effect: dryRun now shows both primary-table before/after examples and a trace that includes documents created via insert (incl. secondary-table writes).