Record the setup-change closeout and the module glossary.

The change notes finish the documentation pass, and CONTEXT.md points at the project specification.

CONTEXT.md

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+# go-dns
+
+Go library for dynamic DNS updates (RFC 2136 / nsupdate-style).
+
+**Canonical spec:** [docs/project-specification.md](./docs/project-specification.md) — follow it for design and implementation.
+
+## Stack
+
+- **Language:** Go (see workspace `go.work` for version)
+- **Module:** `gitea.neitzel.de/konrad/go-dns`
+- **Package:** `godns` (module root)
+- **Type:** Importable Go library (not a standalone service)
+
+## Design (summary)
+
+- Target **BIND** and RFC 2136–compatible authoritative nameservers
+- **Dynamic update** (RFC 2136) and **full zone transfer** (AXFR) over DNS
+- **TSIG** authentication with caller-supplied keys (no key generation in library)
+- Typed **RR builders** per record type (not generic rdata strings)
+- Domain names: **ASCII only** in v1
+- UPDATE: **automatic TCP fallback** on UDP truncation
+- Typed **zone data structures** (`Record`, `Zone`, etc.) for transfer/update results
+- BIND guide: [docs/bind-tsig-configuration.md](./docs/bind-tsig-configuration.md)
+- Project docs override workspace defaults for this module
+
+## Tests
+
+- Unit: `go test ./...`
+- Integration: `go test -tags=integration ./...` — **BIND testcontainer** (Docker required)
+
+## Work tracking
+
+Local markdown issues: [../.scratch/](../.scratch/) — see [docs/agents/issue-tracker.md](../docs/agents/issue-tracker.md).