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>

echo-memory.plugin.src/skills/echo-memory/scripts/vault_lint.py

@@ -165,14 +165,16 @@ def main() -> int:
     # this shared cache instead of issuing a fresh GET per file per section.
     texts = echo.read_many(md_files)
 
-    # Path membership + retired-path detection
+    # Path membership + retired-path detection. Retired patterns are checked FIRST:
+    # a file inside a retired tree is flagged even when a permissive route (the
+    # leaf-README rule) would otherwise match it — previously `archive/x/README.md`
+    # was silently absolved by `leaf-readme` and retired dirs survived unflagged.
     for path in all_files:
-        if routes and not any(rx.match(path) for _, rx in routes):
-            replacement = next((repl for rx, repl in retired if rx.match(path)), None)
-            if replacement is not None:
-                flag("retired-path", f"{path}: retired location — should be {replacement}")
-            else:
-                flag("unknown-path", f"{path}: matches no route in routing.json")
+        replacement = next((repl for rx, repl in retired if rx.match(path)), None)
+        if replacement is not None:
+            flag("retired-path", f"{path}: retired location — should be {replacement}")
+        elif routes and not any(rx.match(path) for _, rx in routes):
+            flag("unknown-path", f"{path}: matches no route in routing.json")
 
     # Per-note frontmatter checks
     template_re = re.compile(r"(^|/)(templates/|.*-template\.md$)")