registry: any registry type name

[fallintoplace]

What

• Resolve Any registry entries by protobuf full name when the incoming type URL has a different prefix.
• Exact URL matches still take priority.

Why

• Type URL prefixes are application-defined, so matching only the full URL can miss a registered message.

Implementation

• Add type-name indexes for JSON and text registries.
• Test custom-prefix lookups and preserve the original URL in JSON round trips.

Benchmark

Not applicable.

[github-actions]

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