Remix BFF: Chain handlers

[ruggi]

Fix #4994

Problem:

As discussed here we need a way to apply middlewares to the Remix API routes.

Fix:

This PR adds the Chain concept to the current handling logic.

• A chain is just an ordered sequence of equivalent handlers
• If a handler throws an exception in the chain, the chain stops
• The last return value of the chain is returned to the client
• The handlers can share state via the chain's context

Notes The diff is large, but it's pure refactoring noise, except for api.server.ts (the very first commit).

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Try me

[relativeci[bot]]

Job #10765: Bundle Size — 62.51MiB (~-0.01%).

6b8d770(current) vs 2296c28 master#10751(baseline)

[!WARNING] Bundle contains 58 duplicate packages – View duplicate packages

Bundle metrics   2 changes 1 regression

	Current Job #10765	Baseline Job #10751
Initial JS	45.75MiB(~+0.01%)	45.75MiB
Initial CSS	0B	0B
Cache Invalidation	20.31%	64.2%
Chunks	35	35
Assets	39	39
Modules	4393	4393
Duplicate Modules	523	523
Duplicate Code	30.95%	30.95%
Packages	467	467
Duplicate Packages	58	58

Bundle size by type   2 changes 1 regression 1 improvement

	Current Job #10765	Baseline Job #10751
JS	62.5MiB (~+0.01%)	62.5MiB
HTML	12.72KiB (-0.39%)	12.77KiB

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View job #10765 report View feat/remix-bff-chain branch activity View project dashboard

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Performance test results: