fix(kb-lint): a wikilink must not resolve into the quarantine

The resolver copied Obsidian's filename-anywhere semantics with a raw rglob, which
walked .AGENTTRASH/ as well. [[log]] therefore stayed "valid" by landing on the
quarantined core/log.md — a page that is out of circulation until a pruning session
and, being gitignored, does not exist on any other machine. The gate reported a
green bundle while pointing readers at a file git does not carry: exactly the #57
failure, hidden by the check that exists to catch it.

Resolution now uses the same filtered set linting uses (pages()), so the two can
never disagree about what exists. A companion test pins that filename-anywhere
resolution for live pages still works, so the narrowing costs nothing; mutating
the resolver back to rglob turns the new test red.

Refs #60

scripts/kb-lint.sh

@@ -20,6 +20,10 @@ def pages():
         if ".AGENTTRASH" not in p.parts:
             yield p
 
+# Names that a wikilink may point at: exactly the pages pages() reports. Deriving this
+# once keeps linting and link resolution from disagreeing about what exists.
+live = {p.stem for p in pages()}
+
 for p in pages():
     rel = p.relative_to(kb)
     text = p.read_text(errors="replace")
@@ -70,9 +74,12 @@ for p in pages():
         if not Path(target).is_file():
             violations.append(f"{rel}: broken relative link -> {m.group(1)}")
     for m in re.finditer(r"\[\[([^\]|#]+)", text):
-        # wikilinks resolve by filename anywhere in the KB (Obsidian semantics)
+        # wikilinks resolve by filename anywhere in the KB (Obsidian semantics) — but only
+        # among pages that BELONG to the bundle. A raw rglob also walked .AGENTTRASH/, so a
+        # link to a quarantined page stayed "valid" here while pointing at nothing on every
+        # other machine (the trash is gitignored). Same exclusion as pages(), one source.
         name = m.group(1).strip().rsplit("/", 1)[-1]
-        if not list(kb.rglob(name + ".md")):
+        if name not in live:
             violations.append(f"{rel}: broken wikilink -> [[{m.group(1).strip()}]]")
 
 for v in violations:

tests/kb-lint.bats

@@ -120,6 +120,28 @@ EOF
   [[ "$output" == *"0 violation(s)"* ]]
 }
 
+@test "a wikilink must not resolve into the quarantine" {
+  # Obsidian resolves [[name]] by filename anywhere under the vault, and the resolver copied
+  # that with a raw rglob — so [[log]] stayed "valid" by landing on the copy waiting in
+  # .AGENTTRASH/. That is #57's failure wearing a green check: the page is out of circulation
+  # until a pruning session with Frank, and it is not even tracked, so on another machine the
+  # link points at nothing while the gate here says it is fine.
+  mkdir -p "$KB/.AGENTTRASH"
+  printf 'no frontmatter, quarantined\n' > "$KB/.AGENTTRASH/log.md"
+  printf -- '---\ntype: reference\n---\nSee [[log]] for the history.\n' > "$KB/good.md"
+  run bash "$LINT" "$KB"
+  [ "$status" -ne 0 ]
+  [[ "$output" == *"broken wikilink -> [[log]]"* ]]
+}
+
+@test "a wikilink to a live page still resolves, in any directory" {
+  # The narrowing above must cost nothing: filename-anywhere semantics is the point.
+  printf -- '---\ntype: reference\n---\nSee [[good]].\n' > "$KB/sub/other.md"
+  run bash "$LINT" "$KB"
+  [ "$status" -eq 0 ]
+  [[ "$output" == *"0 violation(s)"* ]]
+}
+
 @test "the shipped knowledge base itself is conformant" {
   # The tests above exercise the linter against fixtures; nothing else in the
   # suite ever points it at the real bundle, so a page added without frontmatter