fix(selectors): resolve text to the innermost match and scan the root in both forms

an element's text is its whole subtree's text on web and on ios, so every ancestor of a matching element matched too, up to the root. a match a descendant also makes is now dropped, in internal/hierarchy, in the chrome xpath translation and in the page-side web runtime, so all three resolvers name the same element. a raw attribute now matches on a substring (exact for true/false) the way the docs describe, and tree-level FindBySelector considers the root, so ax.find("id:page") and ax.find({id: "page"}) agree.

internal/driver/chrome/testdata/selector-parity.html

@@ -11,5 +11,10 @@
       <div id="customer_row_b2" data-testid="customer-row" aria-label="customer_row_b2, Bob">Bob</div>
       <div id="supplier_row_c3" aria-label="supplier_row_c3, Carol">Carol</div>
     </div>
+    <div id="status_row"><span id="status_badge" data-state="sent-badge">Sent ✓</span></div>
+    <div id="draft_row"><span id="draft_badge">Sent ✓</span></div>
+    <div id="unsent_row"><span id="unsent_badge">3<!-- --> unsent</span></div>
+    <div id="split_row">Sen<span id="split_tail">t here</span></div>
+    <div id="nested_row">Sent <span id="nested_badge">Sent</span></div>
   </body>
 </html>