[littlegrasscao]

Summary

• add GET /shares/{share}/schemas to OpenSharingProtocolService, behind RecipientTokenDecorator
• core ProtocolSchemas returns the distinct shared-as schemas, ordered by name, only when the recipient holds SELECT (ProtocolShares.requireGranted)
• report a missing or ungranted share as RESOURCE_DOES_NOT_EXIST
• reuse bounded maxResults / opaque pageToken pagination, where maxResults=0 returns no items with a token
• add main.hr and main.ops.people to the local catalog for the tests

Testing

• mvn clean install: 134 tests passed
• ProtocolSchemasTest: lists the distinct schemas in a granted share, pages them, and returns an empty list for a granted share with no objects; maxResults=0 returns no schemas but a token

Stacked on #101.