1.6.0 — skills-format migration, lint retired-path fix, plugin.json completeness

Skills migration: each of the eight slash commands gains a skills/<name>/SKILL.md
twin (same invocation name, byte-identical body). Per-skill allowed-tools
pre-authorize the resolved python3/python/py -3 invocations + the CoWork ls
fallback probe; disable-model-invocation: true makes /echo-sweep and /echo-triage
operator-only. Docs-confirmed: a same-name skill takes precedence over the legacy
command, so commands/ coexists until its scheduled 2.0 deletion. The $ECHO
path-resolution dedupe is resolved as not-supported (skill dirs are
self-contained; no cross-skill snippet sharing).

Lint fix: vault_lint.py checks retired patterns BEFORE routes, so a seed README
inside a retired tree (archive/...) flags retired-path instead of being absolved
by the permissive leaf-readme route. New end-to-end regression test seeds
archive/notes/README.md (fails pre-fix, passes now).

plugin.json: version 1.6.0, homepage + repository -> git.alwisp.com/jason/echo.

All suites green: 25/25 client unit tests (incl. routing-sync guard), feature,
reflect, offline-queue, PATCH-semantics. Artifact rebuilt (87 entries, both
formats); pointer refreshed.

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

CHANGELOG.md

@@ -1,5 +1,43 @@
 # Changelog
 
+## 1.6.0
+
+### Changed — the eight slash commands migrated to the skills format
+
+Each `commands/<name>.md` now has a `skills/<name>/SKILL.md` twin with the same
+invocation name and a byte-identical body — confirmed against the current docs
+that a same-name skill **takes precedence** over the legacy command, so both
+formats coexist safely in this release (deleting `commands/` is the 2.0
+packaging break). Done for the features, not the deprecation notice:
+
+- **`allowed-tools` per skill** — the resolved `python3/python/py -3` script
+  invocations (plus the CoWork `ls /sessions/*` fallback probe) are
+  pre-authorized, so `/echo-load`, `/echo-health`, `/echo-recall` etc. stop
+  prompting.
+- **`disable-model-invocation: true`** on the write-heavy entry points
+  (`/echo-sweep`, `/echo-triage`) — only the operator triggers them; the
+  read-side skills stay model-invocable.
+- `argument-hint` / `$ARGUMENTS` carry over unchanged (same semantics in
+  SKILL.md bodies).
+- The `$ECHO` path-resolution block stays per-skill: the skills format has no
+  cross-skill snippet sharing (each skill directory is self-contained per the
+  official docs), and the block is already the 2-line minimum.
+
+### Fixed — lint blind spot: retired trees masked by the leaf-README route
+
+`vault_lint.py` checked retired patterns only for paths matching **no** route,
+so the permissive `leaf-readme` route (`^(.+/)?README\.md$`) absolved any seed
+README inside a retired tree — `archive/` and `_agent/outputs/` survived the
+1.5.0 live cleanup unflagged. Retired patterns are now checked **first**: a
+path in a retired tree flags `retired-path` regardless of what else matches.
+New end-to-end test seeds `archive/notes/README.md` and asserts the flag
+(fails against the pre-fix linter, passes now).
+
+### Added — plugin.json completeness
+
+`homepage` + `repository` → `https://git.alwisp.com/jason/echo`; manifest →
+1.6.0.
+
 ## 1.5.1
 
 ### Fixed — duplicate gate over-firing on vault-common tokens and cross-kind names