Implement private Q2 signal contract and durable reference receiver

Assistant: codex
Assistant-Model: gpt-6-astra
Assistant-Session: 01a06ecb-456a-71c2-b41e-0755d336e883

README.md

@@ -3,8 +3,10 @@
 Observability for Railiance providing monitoring, metrics, alerting etc to
 enable the self-organizing control loop.
 
-**Status: seeded.** `INTENT.md` is written; there is no implementation yet. The
-live cluster currently has no monitoring namespace — this is greenfield.
+**Status: private reference implementation.** A versioned signal contract,
+SQLite receipt/inbox CLI and platform adapter are implemented and tested.
+No monitoring runtime or notification schedule is installed by this work.
+See [the contract and workflow](docs/signal-contract.md).
 
 ## Why this repo exists
 
@@ -23,9 +25,11 @@ carries and surfaces their output.
 3. [`AGENTS.md`](AGENTS.md) — session protocol
 4. `workplans/`
 
-## Open question
+## Placement and verification
 
-Stack-dimension placement (S3 platform capability, or a Quality-dimension
-concern outside the stack) is **undecided** and belongs to `railiance-master`.
-See `INTENT.md` → "Open Placement Question". It is called out explicitly so this
-repo does not drift into the unplaced state `railiance-forge` ended up in.
+Quality dimension, Q2 Observability, as recorded in INTENT/SCOPE. Monitoring
+workload packaging remains outside this repo.
+
+Run `python3 -m unittest discover -s tests -v` (Python 3.11+, no dependencies).
+Live acceptance is tracked by RTEL-WP-0002-T04; local receipts are not external
+operator delivery proof.