chore(planning): archive the custom-decoder-guide bundle (#67)

Ship bookkeeping for PR #67: mark the change shipped (pr: 67, outcome filled),
move the bundle from changes/active/ to changes/archive/, and flip its Index
line from Active to Archived.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: lesnik512

planning/README.md

@@ -70,10 +70,11 @@ carry **no** frontmatter — living prose, dated by git.
 
 ### Active
 
-- **[custom-decoder-guide](changes/active/2026-06-15.01-custom-decoder-guide/change.md)** (2026-06-15) — Docs: a "write your own `ResponseDecoder`" guide for Seam B, mirroring `docs/middleware.md`. Closes deferred item G6.
+_None._
 
 ### Archived (shipped)
 
+- **[custom-decoder-guide](changes/archive/2026-06-15.01-custom-decoder-guide/change.md)** (#67, 2026-06-15) — Docs: a "write your own `ResponseDecoder`" guide for Seam B, mirroring `docs/middleware.md`. Closed deferred item G6.
 - **[audit-doc-fixes](changes/archive/2026-06-14.06-audit-doc-fixes/change.md)** (#66, 2026-06-14) — Closed the [deep-audit](audits/2026-06-14-deep-audit.md) doc-accuracy findings: `Client.stream()` docs, terminal-call attribution, the four auto-raise sites, the pydantic upper bound, and root import paths.
 - **[audit-test-quality](changes/archive/2026-06-14.05-audit-test-quality/change.md)** (#65, 2026-06-14) — Closed 11 [deep-audit](audits/2026-06-14-deep-audit.md) test-quality findings: sync-terminal + CookieConflict coverage, the `StatusError.__init__` invariant, missing status constructions, sync mirrors, typing overloads, a deterministic bulkhead barrier, a pinned budget clock, an observability assertion, and the `TimeoutError` circuit trigger.
 - **[audit-correctness](changes/archive/2026-06-14.04-audit-correctness/change.md)** (#64, 2026-06-14) — Closed 8 [deep-audit](audits/2026-06-14-deep-audit.md) correctness + public-API findings: RetryBudget token ordering, two `OverflowError` crashes, the redaction triple-slash, the msgspec guard, streaming-body symmetry, the RetryBudget docstring caveat, and `middleware/__all__`.

…-06-15.01-custom-decoder-guide/change.md …-06-15.01-custom-decoder-guide/change.mdplanning/changes/active/2026-06-15.01-custom-decoder-guide/change.md renamed to planning/changes/archive/2026-06-15.01-custom-decoder-guide/change.md planning/changes/active/2026-06-15.01-custom-decoder-guide/change.md renamed to planning/changes/archive/2026-06-15.01-custom-decoder-guide/change.md

@@ -1,11 +1,11 @@
 ---
-status: draft
+status: shipped
 date: 2026-06-15
 slug: custom-decoder-guide
 supersedes: null
 superseded_by: null
-pr: null
-outcome: null
+pr: 67
+outcome: Shipped docs/decoders.md (the Seam B "write your own ResponseDecoder" guide); closed deferred item G6.
 ---
 
 # Change: Add a "Writing a custom decoder" guide