deployment: add sepolia-alpha native config override layer

[nimrod-starkware]

Translate the sepolia-alpha config.sequencerConfig overrides (the public
common.yaml + services/*.yaml flat dotted keys) into the nested
sequencer_config.jsonnet override layer the native config builder consumes,
mirroring the existing sepolia-integration layer. Add a regression test
asserting the jsonnet layer stays in lockstep with the combined YAML overrides
(folded: #is_none applied, components dropped).

Co-Authored-By: Claude Opus 4.8 (1M context) noreply@anthropic.com

[reviewable-StarkWare]

This change is 

[nimrod-starkware]

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• apollo_deployments: delete Rust component-config topology mirror #14688
• apollo_deployments,apollo_integration_tests: source harness component configs from jsonnet #14687
• deployment: drop redundant YAML sequencerConfig; source port-uniqueness from jsonnet #14659
• apollo_config,workspace: remove SerializeConfig trait and preset-dump machinery #14654
• apollo_config,apollo_node_config,apollo_config_manager: rework get_config_presentation off dump() #14653
• apollo_node_config,apollo_node: delete CONFIG_POINTERS data and pointer-remap from secrets bin #14652
• apollo_node_config,apollo_config_manager,apollo_integration_tests: retire preset config-generation path #14651
• apollo_node_config,apollo_deployments: assert cross-component equality for formerly-pointer-resolved fields #14650
• apollo_deployments: delete base app_configs and the preset-parity test machinery #14649
• apollo_node_config,apollo_node,deployment: source private_parameters from secrets schema, drop value config schema #14648
• apollo_deployments: retire dead preset/replacer generation machinery #14647
• deployment,apollo_deployments: drop config_format plumbing and retire preset config path #14646
• deployment: add native config layers for the testing overlays #14645
• deployment: add dummy_for_testing native config override layer #14632
• apollo_config: make native the sole config-load path #14631
• apollo_config,apollo_node_config: make config fields with custom deserializers serialize symmetrically #14630
• apollo_integration_tests,apollo_node_config: load integration-test node config via native format #14629
• apollo_deployments: expose jsonnet build() evaluator behind a testing feature #14686
• deployment: extract base-layer start-block numbers into shared constants #14685
• deployment: add mainnet native config override layer #14628
• deployment: add sepolia-alpha native config override layer #14627 👈 (View in Graphite)
• apollo_deployments: test overrides list match #14626
• deployment: add sepolia-integration native config override (chain_params + replacers) #14674
• deployment: add native node-config builder and wire it into the ConfigMap #14609 : 1 other dependent PR (#14655 )
• deployment: thread config_format from CLI to node container arg #14608
• apollo_deployments,deployment: set storage-reader-server ports as constants #14607
• apollo_node: add new CLI arg to parse config #14606
• apollo_deployments: check applicative config matches deployed app_configs #14489 : 2 other dependent PRs (#14480 , #14505 )
• apollo_deployments: assemble and deserialize node config from jsonnet #14487
• apollo_deployments: assemble full node config via build.libsonnet #14486
• apollo_deployments: distributed layout jsonnet test #14485
• apollo_deployments: consolidated layout jsonnet test #14484
• apollo_deployments: test hybrid layout for infra config #14483
• apollo_deployments: introduce hybrid layout for infra config #14482
• apollo_deployments: introduce jsonnet building blocks for infra config #14481
• apollo_deployments: jsonnet applicative config #14479
• main

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PR Summary

Low Risk
Deployment-only sequencer config translation with no runtime code changes; risk is misconfiguration if YAML and jsonnet diverge, which the new test guards against.

Overview
Adds a hybrid native config overlay for the sepolia-alpha sequencer environment so the jsonnet-based config builder can supply the same overrides that today live in YAML config.sequencerConfig.

chain_params.jsonnet carries alpha-specific chain wiring: SN_SEPOLIA, alpha Sepolia feeder/recorder URLs, base-layer block thresholds and contract address, default staking committee, proof-archive bucket starkware-starknet-alpha, and the partial-block-hash checkpoint at block 86311.

replacers.jsonnet holds only non-default tuning: batcher n_concurrent_txs 8, bouncer state_diff_size 5000, and committer inner storage cache 1 GiB.

A new test_sepolia_alpha_native_matches_yaml parity test (same harness as sepolia-integration) locks the bucketed jsonnet to the folded YAML overrides so the two sources cannot drift.

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