Add neutral DataProvider observation SPI

[remdui]

Summary

Prepares the DataProvider-side instrumentation foundation for the 3.3.0 release without coupling DataProvider to OpenTelemetry or HauntedObservability.

• adds a platform-neutral DataProviderObserver / DataProviderObservation SPI and payload-free DataProviderOperationContext
• attaches observers to plugin-bound DataProviderAPI facades rather than a global registry
• propagates observation through scoped facades, database/data-access/schema/messaging handles, and ORM transaction execution
• completes asynchronous observations when returned CompletionStages actually complete
• isolates observer callback failures from the underlying data operation
• deliberately excludes connection identifiers, SQL/query text, keys, destinations, payloads, credentials, player data, and internal UUID registration scopes from the observation contract
• updates the build baseline and reusable Maven-policy workflow to published HauntedPlatform 1.3.0
• documents operation coverage and the privacy/cardinality boundary

Initial operation coverage

• single database registration/removal
• relational, document, key-value and schema API operations
• Pub/Sub and durable-messaging operations
• subscription close/unsubscribe and durable acknowledgement
• ORM transaction execution

Registry lookups, diagnostics, raw JDBC calls, bulk teardown without a single backend type, and internal recovery/health mechanics intentionally remain outside the initial SPI.

Architecture

DataProvider remains OpenTelemetry-free. HauntedObservability can implement this neutral SPI later. The observer is facade-local, propagates to handles issued by that facade, and has a no-op path by default.

Release handling

This feature PR intentionally keeps the reactor at 3.2.0. After merge, DataProvider's existing guarded update_version.sh minor flow should create the dedicated 3.3.0 release commit and v3.3.0 tag, keeping the root revision, Velocity annotation, and README dependency examples synchronized.