Update to Camberstack: Google Ads

SKILL.md text changes

− removed · + added

--- before
+++ after
@@ -5,19 +5,21 @@
 
 # Using Camberstack
 
-Camberstack connects the user's Google Ads account (and, optionally, Search Console and Google Analytics 4).
+Camberstack connects the user's Google Ads account and, optionally, Search Console, Google Analytics 4 and Merchant Center (for products and Shopping, start with `merchant_accounts`, not `list_accounts`).
 
 1. **Start with `list_accounts`.** Answer questions with `account_overview` and `run_gaql` (read-only GAQL `SELECT`).
 2. **To change something:** call the `propose_` tool for that change (`propose_pause_campaign`,
    `propose_set_daily_budget`, `propose_mark_key_event`, …), show the user the summary, including any ⚠ line, and ask
    for approval. Only then call `apply_changes`.
 3. **Never call `apply_changes` unless the user has explicitly approved that specific proposal in this conversation.**
-   Every applied proposal can be reversed with `propose_undo`, which makes a reversing proposal to approve and apply;
+   Applied proposals can be reversed with `propose_undo`, which makes a reversing proposal to approve and apply, except
+   deletions Google can't reverse: their summary says so with a ⚠, so tell the user before they approve;
    `change_history` lists what was applied.
-4. **Each Google service is added separately.** When a result says Search Console or Analytics isn't part of the
+4. **Each Google service is added separately.** When a result says Search Console, Analytics or Merchant Center isn't part of the
    connection, give the user its `grant_url` (one click adds it). Never tell them to reconnect.
 5. For `keyword_ideas` and `keyword_metrics`, pass the account's own market: `location_ids` default to the United States.
-6. **Search Console is read-only.** Lead with `search_console_summary` (per-query rows leave out rare queries).
-   Camberstack can't request indexing or submit sitemaps; the user does that in Search Console.
+6. **Search Console:** lead with `search_console_summary` (per-query rows leave out rare queries). Sitemaps and
+   properties change through proposals (`propose_submit_sitemap`, `propose_delete_sitemap`, `propose_add_site`,
+   `propose_remove_site`). Camberstack can't request indexing or verify a property; the user does those in Search Console.
 7. **Account 000-000-0001 is a demo** with sample data: anyone can try every tool on it, and changes there never
    touch Google. Always say when you are using it.