refactor(socket): extract protocol handlers

[AlCalzone]

Moves Socket.IO request handling into typed protocol modules.

• Keeps event names, rooms, acknowledgement envelopes, argument order, timing, and dynamic API behavior unchanged.
• Resolves collaborators per call so restarts cannot leave stale handlers.
• Review focus: wire compatibility, first/last-client lifecycle, and production persistence paths.

Part of #4722. Stacked on #4727.

[coveralls]

Coverage Report for CI Build 29565570304

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No base build found for commit a45df40 on alcalzone-backend-refactor-http-runtime.
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Coverage: 40.578%

Details

• Patch coverage: 13 uncovered changes across 4 files (118 of 131 lines covered, 90.08%).

Uncovered Changes

File	Changed	Covered	%
api/socket/znifferApi.ts	29	21	72.41%
api/socket/mqttApi.ts	15	12	80.0%
api/socket/hassApi.ts	30	29	96.67%
api/socket/registerSocketApi.ts	16	15	93.75%
Total (8 files)	131	118	90.08%

Coverage Regressions

Requires a base build to compare against. How to fix this →

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Coverage Stats

Relevant Lines:	6805
Covered Lines:	2953
Line Coverage:	43.39%
Relevant Branches:	4339
Covered Branches:	1569
Branch Coverage:	36.16%
Branches in Coverage %:	Yes
Coverage Strength:	26.82 hits per line

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💛 - Coveralls