clean up run-protocol exports

[turadg]

refs: #4800

Description

Reduce exports of @agoric/run-protocol package to reduce churn in #5802

I tried to stop exporting src/ and just src/proposals/, but the latter depends on files in the former. (Detected by getting-started (local-npm) test.) Deferred solving to #5808

• figure out what to do with

  agoric-sdk/packages/SwingSet/misc-tools/measure-metering/measure.js

  Lines 52 to 55 in 0c130b3

  	const autoswapFn = new URL(
  	'../../../run-protocol/src/vpool-xyk-amm/multipoolMarketMaker.js',
  	import.meta.url,
  	).pathname;

Security Considerations

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Documentation Considerations

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Testing Considerations

Might break some downstream. I'll clean those up.