feat(tracing): integrate shared error ownership classifier

[jshaikScale]

Summary

• consume the neutral classifier from scale-gp-beta PR #183 through a thin Agentex adapter
• ignore generic Agentex wrappers/orchestration and own only narrow managed subsystems
• classify sync, async, and ADK exceptions from their original traceback without changing propagation
• forward safe category source, classifier version, and deterministic rule ID to SGP

Conservative Agentex policy

Platform-owned prefixes:

• agentex.lib.core.tracing.processors — Agentex-owned trace export delivery
• agentex.lib.core.tracing.span_queue — Agentex-owned trace queue/export transport
• agentex.lib.core.adapters.streams.adapter_redis — managed Redis stream transport and persistence

Ignored prefixes:

• agentex — generic tracing, orchestration, callback, workflow, and wrapper frames do not establish responsibility
• sqlalchemy, pyodbc, psycopg, psycopg2, asyncpg, redis — database/client frames defer to the nearest meaningful owner

Specific platform prefixes beat the broad ignored agentex prefix in the shared engine. No package root is globally platform-owned.

Database behavior

• application/business caller → driver failure = application
• managed Redis stream persistence → driver failure = platform
• driver-only or ambiguous traceback = unknown
• application validation/query construction invoked through a managed wrapper remains application when the application frame or an authoritative typed/explicit signal proves ownership

Dependency status

This PR does not vendor the engine or invent a package version. It remains draft and blocked on merge/publication of the shared SDK API. Standalone CI is expectedly red until that release can be consumed normally.

Validation against shared source

• 185 passed, 2 skipped — full relevant Agentex tracing, ADK, and processor suite
• Ruff lint and format checks passed
• Pyright: 0 errors, 0 warnings, 0 informations
• focused mypy: Success: no issues found in 2 source files
• git diff --check passed

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