fix(kyberforge): fix bats SCRIPT path and clarify test helper install location

Both validate.bats and new-skill.bats constructed SCRIPT using
$(dirname "$BATS_TEST_FILENAME"), which resolves to tests/ — causing
every test to fail with file-not-found. Fixed to use
$BATS_TEST_DIRNAME/../scripts/ to reach the actual scripts/ directory.

Also clarifies that bats-support/bats-assert must be installed from the
repo root (not the skill root) to match where the tests load them from,
and adds text language tags to three output-template code blocks in
skill-audit's SKILL.md.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plugins/kyberforge/skills/skill-write/tests/new-skill.bats

@@ -5,7 +5,7 @@ setup() {
     load "$REPO_ROOT/tests/test_helper/bats-support/load"
     load "$REPO_ROOT/tests/test_helper/bats-assert/load"
 
-    SCRIPT="$(cd "$(dirname "$BATS_TEST_FILENAME")" && pwd)/new-skill.sh"
+    SCRIPT="$(cd "$BATS_TEST_DIRNAME/../scripts" && pwd)/new-skill.sh"
     DEST="$(mktemp -d)"
 }