feat(config): wire startup through resolveConfig

[spypsy]

Wires the aztec start startup path through resolveConfig, replacing the legacy process.env-as-merged-blob path now that the resolver and adapters from A-989/A-990 exist.

Summary

• Build cli / env / network layers in the action handler and call resolveConfig.
• Stop registering Commander defaults from env/mappings at registration time; argv → cliToTyped → resolveConfig.
• Drop the manual --network pre-parse and remote-network env enrichment in bin/index.ts; remove enrichEnvironmentWithNetworkConfig, enrichEnvironmentWithChainName, enrichVar.
• Replace getConfigEnvVars() + extractRelevantOptions() merges in start_node, start_prover_broker, start_prover_agent, start_bot, start_p2p_bootstrap with per-component resolveConfig(mappings, namespace).
• Extract OwnLocalNetworkConfig + localNetworkConfigMappings into a light local-network/config.ts and auto-generate --localNetwork.* flags via getOptions('localNetwork', localNetworkCliConfigMappings). Genesis state config (testAccounts, sponsoredFPC, prefundAddresses) is exposed there since it only matters during fresh-chain init.
• Add resolvedToConfig<T> foundation helper and put ConfigLayerName.DEFAULT directly into ORDERED_CONFIG_LAYERS so layer extraction is uniform.
• Rename getConfigFromMappings → buildConfigFromEnv everywhere; it now reflects what it actually does (env + mapping defaults, no CLI / no network).

Notable change

• Network config is no longer mutated into process.env; remote NetworkConfig is passed through networkConfigToTyped as an explicit NETWORK layer.

Fixes A-991

Test plan

• Unit tests in aztec_start_options.test.ts, config_resolver.test.ts, cli/src/config/network_config.test.ts, foundation config.test.ts.
• CI: e2e suites exercise aztec start --local-network and node startup.