chore!: remove telemetry API usage (#3815)

# What does this PR do?

remove telemetry as a providable API from the codebase. This includes
removing it from generated distributions but also the provider registry,
the router, etc

since `setup_logger` is tied pretty strictly to `Api.telemetry` being in
impls we still need an "instantiated provider" in our implementations.
However it should not be auto-routed or provided. So in
validate_and_prepare_providers (called from resolve_impls) I made it so
that if run_config.telemetry.enabled, we set up the meta-reference
"provider" internally to be used so that log_event will work when
called.

This is the neatest way I think we can remove telemetry from the
provider configs but also not need to rip apart the whole "telemetry is
a provider" logic just yet, but we can do it internally later without
disrupting users.

so telemetry is removed from the registry such that if a user puts
`telemetry:` as an API in their build/run config it will err out, but
can still be used by us internally as we go through this transition.


relates to #3806

Signed-off-by: Charlie Doern <cdoern@redhat.com>

llama_stack/distributions/open-benchmark/build.yaml

@@ -16,8 +16,6 @@ distribution_spec:
     - provider_type: inline::llama-guard
     agents:
     - provider_type: inline::meta-reference
-    telemetry:
-    - provider_type: inline::meta-reference
     eval:
     - provider_type: inline::meta-reference
     datasetio:

llama_stack/distributions/open-benchmark/open_benchmark.py

@@ -105,7 +105,6 @@ def get_distribution_template() -> DistributionTemplate:
         ],
         "safety": [BuildProvider(provider_type="inline::llama-guard")],
         "agents": [BuildProvider(provider_type="inline::meta-reference")],
-        "telemetry": [BuildProvider(provider_type="inline::meta-reference")],
         "eval": [BuildProvider(provider_type="inline::meta-reference")],
         "datasetio": [
             BuildProvider(provider_type="remote::huggingface"),

llama_stack/distributions/open-benchmark/run.yaml

@@ -7,7 +7,6 @@ apis:
 - inference
 - safety
 - scoring
-- telemetry
 - tool_runtime
 - vector_io
 providers:
@@ -76,13 +75,6 @@ providers:
       responses_store:
         type: sqlite
         db_path: ${env.SQLITE_STORE_DIR:=~/.llama/distributions/open-benchmark}/responses_store.db
-  telemetry:
-  - provider_id: meta-reference
-    provider_type: inline::meta-reference
-    config:
-      service_name: "${env.OTEL_SERVICE_NAME:=\u200B}"
-      sinks: ${env.TELEMETRY_SINKS:=}
-      otel_exporter_otlp_endpoint: ${env.OTEL_EXPORTER_OTLP_ENDPOINT:=}
   eval:
   - provider_id: meta-reference
     provider_type: inline::meta-reference