docs(telemetry): correct tier from 5 to 1

telemetry has zero micro-lib dependencies — only the external OTel SDK.
Tier 1 reflects its actual position in the dependency graph. The Tier 5
label was misleading about push/tag ordering; telemetry can be released
independently of all other micro-lib modules.

CLAUDE.md

@@ -8,7 +8,7 @@ Sets the three OTel global providers so that all micro-libs using the OTel globa
 
 ## Tier & Dependencies
 
-**Tier 5** (application bootstrap only). Must never be imported by framework libraries (Tier 0–4).
+**Tier 1** (no micro-lib dependencies; external OTel SDK only). Must never be imported by framework libraries.
 
 Depends on:
 - `go.opentelemetry.io/otel` and sub-packages — API and SDK
@@ -21,7 +21,7 @@ No micro-lib dependencies. No `launcher` dependency — telemetry has no Compone
 
 ## Key Design Decisions
 
-- **Tier 5 / app-only** (ADR-001): Libraries use only the OTel API (no-op default). This module activates the real SDK. Importing it from a library is a mistake.
+- **Tier 1 / app-only** (ADR-001): Libraries use only the OTel API (no-op default). This module activates the real SDK. Importing it from a library is a mistake.
 - **Three-signal OTLP bootstrap** (ADR-002): `New(ctx, cfg)` sets up traces → Tempo, metrics → Mimir, logs → Loki, all over a single OTLP gRPC endpoint. W3C TraceContext + Baggage propagation is set globally.
 - **Global provider strategy** (ADR-003): Libraries call `otel.Tracer(...)` / `otel.Meter(...)` / `global.Logger(...)`. After `telemetry.New`, those calls route to the real SDK with no library changes required.
 - **No `launcher.Component`**: Telemetry is not a lifecycle component. The caller defers the returned shutdown function directly in `main`. This keeps the module dependency graph minimal and the interface simple.