feat(migrations): add plugin-owned Hermes import

* feat: add migration providers

* feat: offer Hermes migration during onboarding

* feat(hermes): map imported config surfaces

* feat(onboard): require fresh migration imports

* docs(cli): clarify Hermes import coverage

* chore(migrations): rename Hermes importer package

* chore(migrations): rewire Hermes importer id

* fix(migrations): redact migration JSON details

* fix(hermes): use provider runtime for config imports

* test(hermes): cover missing source planning

---------

Co-authored-by: Peter Steinberger <steipete@gmail.com>

scripts/lib/plugin-sdk-entrypoints.json

@@ -94,6 +94,8 @@
   "testing",
   "temp-path",
   "logging-core",
+  "migration",
+  "migration-runtime",
   "markdown-table-runtime",
   "account-helpers",
   "account-core",