Seed INTENT, SCOPE, README for the observability layer

Fills the gap identified in the 2026-08-11 Railiance architecture assessment:
five layers declare they intend to be self-evidencing or auditable, and nothing
owned the place that evidence goes. The live cluster has no monitoring
namespace at all.

Positions telemetry as the evidence plane - it owns the signal, not the meaning
of the signal, so conformance rules stay with the repos that own them. Flags
stack-dimension placement as an open question for railiance-master rather than
asserting a level, so this repo does not repeat railiance-forge's unplaced
state.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

SCOPE.md

@@ -0,0 +1,103 @@
+# SCOPE
+
+> This file helps you quickly understand what this repository is about,
+> when it is relevant, and when it is not.
+> It is intentionally lightweight and may be incomplete.
+
+---
+
+## One-liner
+
+Observability for Railiance — monitoring, metrics, logs, traces, and alerting that turn running behaviour into evidence and give the self-organizing control loop a signal to close on.
+
+---
+
+## Core Idea
+
+Five Railiance layers independently declare that they intend to be
+"self-evidencing" or "auditable". None of them owned the place that evidence
+goes, and the live cluster has no monitoring namespace at all. This repo fills
+that gap: it is the evidence plane the rest of the stack emits into.
+
+The distinction that keeps this repo honest: it owns **the signal**, not
+**the meaning of the signal**. Conformance rules and consistency checks belong
+to the repos that own those concerns; telemetry carries and surfaces their
+output.
+
+---
+
+## In Scope
+
+- Metrics collection, storage, and query
+- Log aggregation and retention
+- Tracing substrate
+- Alerting rules, routing, and notification paths
+- Dashboards and operator/agent-facing health surfaces
+- The standard emission contract other Railiance layers implement
+- Retention policy sufficient to prove restore drills and rollout holds
+- Signal exposure that automated control loops consume
+
+---
+
+## Out of Scope
+
+- Conformance and declaration-validation *rules* — owned by the repos whose
+  declarations they check (`railiance-master`, family declaration validator)
+- The monitoring stack as a deployable package → `rapp-*` territory
+- Immutable audit custody — a separate concern with separate guarantees
+- Business, cost, and revenue analytics → `resource-control`, `fin-hub`
+- Incident management, on-call rotation, paging policy
+- Secret material of any kind (this layer is explicitly non-custodial)
+
+---
+
+## Relevant When
+
+- A layer needs somewhere to emit health, readiness, or drift signal
+- An expectation should raise an alert when violated
+- A control loop needs a signal to close on
+- Proving after the fact that a restore, rollout, or migration actually held
+
+## Not Relevant When
+
+- Defining what "correct" means for a declaration (that is the owning repo's job)
+- Packaging the monitoring workload for deployment (that is `rapp-*`)
+- Storing anything sensitive
+
+---
+
+## Current State
+
+- Status: **seeded** — `INTENT.md` written 2026-08-11, no implementation yet
+- The live cluster has no monitoring namespace; this is greenfield
+- Open: stack-dimension placement is undecided (see `INTENT.md`, "Open
+  Placement Question") and belongs to `railiance-master`
+
+---
+
+## How It Fits
+
+- Upstream dependencies: `railiance-cluster` (S2) for runtime,
+  `railiance-platform` (S3) for any stateful backing services it needs
+- Downstream consumers: every layer that declares itself self-evidencing, plus
+  automated control loops and agent planning surfaces
+- Often used with: `railiance-master` (which owns what the signals must prove),
+  `railiance-fabric` (graph and blast-radius context for an alert)
+
+---
+
+## Terminology
+
+- Preferred terms: evidence plane, emission contract, expectation-based alerting
+- Potentially confusing: "self-evidencing" is a property *other* layers aspire
+  to; this repo provides the substrate that makes it checkable, it does not
+  make the claims on their behalf
+
+---
+
+## Getting Oriented
+
+- Start with: `INTENT.md`
+- Then: `SCOPE.md`, `AGENTS.md`, `workplans/`
+- Context: `railiance-platform/history/2026-08-11-railiance-architecture-in-aspiration.md`
+  records the assessment that identified this gap