One configuration API to rule them all

[trask]

Now that we have a real configuration API, let's consolidate!

This PR shows end-to-end that we can delete all of the other configuration APIs and bridges.

ConfigProperties still needs to live, but only during SDK autoconfiguration.

Then we can bridge ConfigProperties and use the declarative configuration API everywhere else.

This PR shows the final result.

Planning to break this PR into smaller pieces:

                               ┌─(B)─> AgentInstrumentationConfig (11 PRs) ──> Delete (1 PR)
                               │       - aws, database, redis,                 - AgentInstrumentationConfig,
                               │         messaging, logging,                     (agent) ConfigPropertiesBridge
                               │         graphql-grpc, web, async,
                               │         http, annotations, other
                               │
                               ├─(C)─> Delete AgentConfig (1 PR)
                               │
                               ├─(D)─> CommonConfig (1 PR) ──> CommonConfig (4 PRs) ──> Delete (1 PR)
                               │       - Foundation            - http-clients,          - CommonConfig,
                               │                                 http-servers,            AgentCommonConfig,
                               │                                 database,                EnduserConfig
                               │                                 other
                               │
(A) Agent Foundation (1 PR) ───┼─(E)─> ExperimentalConfig (4 PRs) ──> Delete (1 PR)
    - Reverse bridge,          │       - controller-view,             - ExperimentalConfig
      DeclarativeConfigUtil    │         messaging,
                               │         indy, other
                               │
                               ├─(F)─> Extension APIs (3 PRs)
                               │       - IgnoredTypesConfigurer,
                               │         InstrumentationModule,
                               │         AgentExtension
                               │
                               └─(G)─> Spring Boot (1 PR) ──> Spring Boot (5 PRs) ──> Delete (1 PR)
                                       - Foundation           - http-clients,         - InstrumentationConfigUtil,
                                                                http-servers,           (spring) ConfigPropertiesBridge
                                                                database,
                                                                messaging, other

(H) Clean up (1 PR)
    - Delete InstrumentationConfig

UPDATE: remaining todos

(checked means either done, or issue created, or PR exists)

• [x] consider reworking/consolidating AgentConfig - last usage is instrumentationMode() - so that will be cleaned up with https://github.com/open-telemetry/opentelemetry-java-instrumentation/issues/15796
• [ ] consider reworking/consolidating AgentCommonConfig - fine as is for @zeitlinger
• [ ] consider reworking/consolidating EarlyInitAgentConfig - fine as is for @zeitlinger
• [x] centralize all access to agent configuration node in case we decide to move it under the distribution where we won't be able to access it normally via Declarative Configuration API: created https://github.com/open-telemetry/opentelemetry-java-instrumentation/issues/15807
• [x] delete InstrumentationConfig
• [x] spring starter's LogbackAppenderInstaller still needs to be updated to use declarative config somehow: https://github.com/open-telemetry/opentelemetry-java-instrumentation/issues/15812
• [x] remaining extension API InstrumentationModule
• [x] remaining extension API AgentExtension: https://github.com/open-telemetry/opentelemetry-java-instrumentation/issues/15798
• [x] delete both DeprecatedConfigProperties (may need something like this in the future, but will need to be rewritten to support declarative configuration anyways) - only remaining usage is in LogbackAppenderInstaller: https://github.com/open-telemetry/opentelemetry-java-instrumentation/issues/15812
• [x] deprecate DeclarativeConfigPropertiesBridge with a warning on usage (need a deprecation cycle since distros and extensions may be relying on it): https://github.com/open-telemetry/opentelemetry-java-instrumentation/issues/15811
• [x] ensure all remaining usages of ConfigProperties have been deprecated and can be removed in 3.0
• [x] IgnoredTypesConfigurer: https://github.com/open-telemetry/opentelemetry-java-instrumentation/issues/15806