fix(native): Hoist plugin loading and de-inline factory map for dynamic connector support

[20001020ycx]

Description

• Hoist registerDynamicFunctions() before registerVeloxConnectors() in PrestoServer.cpp
• De-inline connector factory registration functions from Registration.h into Registration.cpp

Motivation and Context

This PR enables dynamic connector plugins — connectors loaded at runtime via plugin-dir using dlopen() — as described in RFC-0019: Connector Plugins. Two changes are needed to make this work correctly.

Both changes revolve around a singleton factory map defined in Registration.cpp:

static std::unordered_map<std::string, std::shared_ptr<ConnectorFactory>> factories;

This map lives inside detail::connectorFactories() and maps connector names (e.g. "hive", "tpch") to their ConnectorFactory instances. Both registerConnectorFactory(name, factory) and getConnectorFactory(name) read and write this map.

Why registerDynamicFunctions() must be hoisted before registerVeloxConnectors()

registerVeloxConnectors() iterates over every *.properties file in the catalog/ directory. For each one, it reads connector.name and calls getConnectorFactory(connectorName) to look up the factory in the singleton map, then calls factory->newConnector(...) to instantiate the connector.

registerDynamicFunctions() loads plugin .so files from the plugin/ directory via dlopen(). Each plugin's registerExtensions() entry point calls registerConnectorFactory(...) to insert its factory into the same singleton map.

Before this PR, registerVeloxConnectors() ran before registerDynamicFunctions(). Since plugins had not been loaded yet, the factory map had no entry for dynamically registered connector names. When registerVeloxConnectors() processed a catalog .properties file referencing a dynamic connector, getConnectorFactory() threw because the corresponding factory had not been registered yet.

So the sequence must be:

1. registerDynamicFunctions() — loads plugin .so files, plugins call registerConnectorFactory() to insert into the map
2. registerVeloxConnectors() — reads catalog/*.properties, calls getConnectorFactory() to look up entries in the map

The original code had no problem with built-in connectors (Hive, TPC-H, etc.) because their factories are registered statically at compile time.

Why registration functions must be de-inlined

Before this PR, the factory map was a static local variable inside the inline function connectorFactories() in Registration.h. Any connector shared library that #includes this header gets its own copy of the static variable, meaning both presto_server and the plugin library hold separate factory maps (Note, shared library references the header file in the presto-native-execution for compilation, the implementation are resolved at run time):

presto_server           → factory map at 0xAAAA  {"hive": ..., "tpch": ...}
libpresto_plugin.so     → factory map at 0xBBBB  {"my_connector": ...}

This breaks the singleton property of the factory map: the plugin's registerConnectorFactory() inserts into its own map (0xBBBB), but the server's getConnectorFactory() reads from its own map (0xAAAA) — and finds nothing.

De-inlining connectorFactories() ensures the static local variable exists in exactly one place (Registration.cpp, linked into presto_server), allowing dynamically registered connector known to presto_server successfully.

Test Plan

• Build presto_server with the changes
• End-to-end tested with a customized native connector shared library (.so) loaded via plugin-dir, verifying successful connector registration and query execution.

Release Notes

== NO RELEASE NOTE ==

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