[2.26.x] DDF-6714 add plugin support to websockets

[glenhein]

What does this PR do?

Add plugin support to websockets so downstream projects inject special processing logic for web socket connections.

Who is reviewing it?

@rececoffin @jlcsmith

Select relevant component teams:

Ask 2 committers to review/merge the PR and tag them here.

@derekwilhelm

How should this be tested?

Build, install, and make sure existing web socket behavior functions as expected.

Any background context you want to provide?

What are the relevant tickets?

Fixes: #6714

Screenshots

Checklist:

• [ ] Documentation Updated
• [ ] Update / Add Threat Dragon models
• [ ] Update / Add Unit Tests
• [ ] Update / Add Integration Tests

Notes on Review Process

Please see Notes on Review Process for further guidance on requirements for merging and abbreviated reviews.

Review Comment Legend:

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• ❗ (Exclamation Mark) This comment is critical and requires clarification or action before approval.

[jlcsmith]

build now

[cxddfbot]

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[cxddfbot]

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