feat: fetch add wait_until parameter for page loads options

Add `--wait_until` and `--wait_ms` CLI arguments to configure session wait behavior. Updates `Session.wait` to evaluate specific page load states (`load`, `domcontentloaded`, `networkidle`, `fixed`) before completing the wait loop.

src/cdp/cdp.zig

@@ -131,7 +131,7 @@ pub fn CDPT(comptime TypeProvider: type) type {
         // timeouts (or http events) which are ready to be processed.
         pub fn pageWait(self: *Self, ms: u32) Session.WaitResult {
             const session = &(self.browser.session orelse return .no_page);
-            return session.wait(ms);
+            return session.wait(ms, .load);
         }
 
         // Called from above, in processMessage which handles client messages

src/cdp/domains/lp.zig

@@ -280,7 +280,7 @@ test "cdp.lp: action tools" {
     const page = try bc.session.createPage();
     const url = "http://localhost:9582/src/browser/tests/mcp_actions.html";
     try page.navigate(url, .{ .reason = .address_bar, .kind = .{ .push = null } });
-    _ = bc.session.wait(5000);
+    _ = bc.session.wait(5000, .load);
 
     // Test Click
     const btn = page.document.getElementById("btn", page).?.asNode();

src/cdp/testing.zig

@@ -136,7 +136,7 @@ const TestContext = struct {
                 0,
             );
             try page.navigate(full_url, .{});
-            _ = bc.session.wait(2000);
+            _ = bc.session.wait(2000, .load);
         }
         return bc;
     }