feat(cli): coordinate click + command aliases + clearer find error (issue #8.4)

Field-report ergonomics fixes so agents stop wasting a round on a wrong guess:

- Coordinate click is now first-class: `click <x> <y>`, `click <x>,<y>`,
  and `click --coords <x>,<y>` dispatch a raw viewport-point click (no
  element resolution), reusing the humanize trajectory + press dwell. Was
  previously only reachable via eval(elementFromPoint(...).click()).
- Aliases: `tabs` (plural) → the `tab` subcommand tree; `get-text`/`get_text`
  → `get text <selector>`.
- `find <value> <action>` with a bare value (no locator keyword), e.g.
  `find "I'm not a robot" click`, now errors with the corrected command
  (`find text "I'm not a robot" click`) plus concrete examples, instead of
  a bare "Valid options: role, text, ..." list.

Adds parse-layer regression tests for every form.

cli/src/native/interaction.rs

@@ -1143,6 +1143,20 @@ async fn wait_for_paint_settled(client: &CdpClient, session_id: &str) {
     .await;
 }
 
+/// Click at a raw viewport coordinate, bypassing element/selector resolution
+/// (issue #8.4 first-class coordinate click). Honors the humanize trajectory and
+/// press dwell exactly like a selector click — it shares `dispatch_click`.
+pub async fn click_at_point(
+    client: &CdpClient,
+    session_id: &str,
+    x: f64,
+    y: f64,
+    button: &str,
+    click_count: i32,
+) -> Result<(), String> {
+    dispatch_click(client, session_id, x, y, button, click_count).await
+}
+
 async fn dispatch_click(
     client: &CdpClient,
     session_id: &str,