chore: update vendored skills and record provenance

humanizer 2.2.0 -> 2.9.1 (blader/humanizer, MIT): adds a Voice
Calibration section and a passive-voice pattern, reworks negative
parallelisms and em dashes. Version moved to metadata.version upstream.

impeccable 3.6.0 -> 4.0.4 (pbakaus/impeccable, Apache-2.0): the repo
tags the skill and the npm CLI separately, so 3.6.0 was a real release
and npm's 3.5.0 was never the comparison. Adds native-platform reference
briefs.

Each now carries an UPSTREAM file; bin/check-vendored.sh reports drift.

skills/impeccable/scripts/live/event-validation.mjs

@@ -5,17 +5,26 @@
 
 import { canCreateInsert } from './insert-ui.mjs';
 
-// The accepted visual action values come from the canonical vocabulary so the
-// validator, the picker UI, and the marketing demo never drift. Imported (not
-// just re-exported) so it is also in scope for the validators below.
-import { VISUAL_ACTIONS } from './vocabulary.mjs';
-export { VISUAL_ACTIONS };
+// The accepted protocol values come from the canonical vocabulary so the
+// validator, the store, the server, and the picker UI never drift. Imported
+// (not just re-exported) so they are also in scope for the validators below.
+import { AGENT_PHASES, CLIENT_EVENT_TYPES, VISUAL_ACTIONS } from './vocabulary.mjs';
+export { AGENT_PHASES, CLIENT_EVENT_TYPES, VISUAL_ACTIONS };
+
+const AGENT_PHASE_SET = new Set(AGENT_PHASES);
 
 const ID_PATTERN = /^[0-9a-f]{8}$/;
 const VARIANT_ID_PATTERN = /^[0-9]{1,3}$/;
 const INSERT_POSITIONS = new Set(['before', 'after']);
 const FORBIDDEN_MANUAL_EDIT_TEXT_CHARS = ['<', '{', '}', '`'];
 
+// Mount acknowledgements carry a module URL and a raw exception message from
+// the page. Both are attacker-adjacent (any script on the page can POST them
+// with the token it can already read), so they are length-capped before they
+// reach the journal.
+export const MOUNT_URL_MAX_LENGTH = 2000;
+export const MOUNT_ERROR_MAX_LENGTH = 1000;
+
 function isValidId(v) { return typeof v === 'string' && ID_PATTERN.test(v); }
 function isValidVariantId(v) { return typeof v === 'string' && VARIANT_ID_PATTERN.test(v); }
 
@@ -92,6 +101,36 @@ function validateManualEditEvent(msg, label) {
   return null;
 }
 
+function isValidMountVariant(value) {
+  return Number.isInteger(value) && value >= 1 && value <= 999;
+}
+
+/**
+ * Mount acknowledgements are the browser's answer to "did the thing you
+ * published actually render". They are validated strictly because the render
+ * truth in the session snapshot is built from them: a malformed ack that slid
+ * through would report a variant as mounted that never was.
+ */
+function validateMountAck(msg) {
+  if (!isValidId(msg.id)) return 'variant_mounted: missing or malformed id';
+  if (!isValidMountVariant(msg.variant)) return 'variant_mounted: variant must be an integer 1-999';
+  if (msg.url !== undefined) {
+    if (typeof msg.url !== 'string') return 'variant_mounted: url must be string';
+    if (msg.url.length > MOUNT_URL_MAX_LENGTH) return 'variant_mounted: url too long';
+  }
+  return null;
+}
+
+function validateMountFailure(msg) {
+  if (!isValidId(msg.id)) return 'variant_mount_failed: missing or malformed id';
+  if (!isValidMountVariant(msg.variant)) return 'variant_mount_failed: variant must be an integer 1-999';
+  if (typeof msg.url !== 'string' || !msg.url.trim()) return 'variant_mount_failed: url required';
+  if (msg.url.length > MOUNT_URL_MAX_LENGTH) return 'variant_mount_failed: url too long';
+  if (typeof msg.error !== 'string' || !msg.error.trim()) return 'variant_mount_failed: error required';
+  if (msg.error.length > MOUNT_ERROR_MAX_LENGTH) return 'variant_mount_failed: error too long';
+  return null;
+}
+
 export function validateEvent(msg) {
   if (!msg || typeof msg !== 'object' || !msg.type) return 'Missing or invalid message';
   switch (msg.type) {
@@ -118,6 +157,23 @@ export function validateEvent(msg) {
         return 'checkpoint: paramValues must be an object';
       }
       return null;
+    case 'agent_phase':
+      if (!isValidId(msg.id)) return 'agent_phase: missing or malformed id';
+      if (typeof msg.phase !== 'string' || !msg.phase) return 'agent_phase: missing phase';
+      // The enum, not a shape pattern. A phase the browser cannot rank is a
+      // phase the progress bar cannot show, so accepting an arbitrary
+      // lowercase word only defers the failure to the UI.
+      if (!AGENT_PHASE_SET.has(msg.phase)) {
+        return 'agent_phase: unknown phase ' + msg.phase + ' (expected one of ' + AGENT_PHASES.join(', ') + ')';
+      }
+      if (msg.durationMs !== undefined && (!Number.isFinite(msg.durationMs) || msg.durationMs < 0)) {
+        return 'agent_phase: durationMs must be a non-negative number';
+      }
+      return null;
+    case 'variant_mounted':
+      return validateMountAck(msg);
+    case 'variant_mount_failed':
+      return validateMountFailure(msg);
     case 'exit':
       return null;
     case 'prefetch':
@@ -131,6 +187,12 @@ export function validateEvent(msg) {
       if (msg.message.length > 4000) return 'steer: message too long';
       if (msg.pageUrl !== undefined && typeof msg.pageUrl !== 'string') return 'steer: pageUrl must be string';
       return null;
+    case 'carbonize_cleanup':
+      if (!isValidId(msg.id)) return 'carbonize_cleanup: missing or malformed id';
+      if (!isValidId(msg.sessionId)) return 'carbonize_cleanup: missing or malformed sessionId';
+      if (!msg.file || typeof msg.file !== 'string') return 'carbonize_cleanup: missing file';
+      if (!isValidVariantId(String(msg.variantId))) return 'carbonize_cleanup: missing or malformed variantId';
+      return null;
     default:
       return 'Unknown event type: ' + msg.type;
   }