feat(cdp): implement Network.setCookie + deleteCookies, full field fidelity (#170)

* feat(cdp): implement Network.setCookie + deleteCookies, full field fidelity

Closes #168.

Adds the missing Network.setCookie (singular) and Network.deleteCookies
methods and upgrades the existing Network.setCookies/getCookies handlers
so sameSite, expires, httpOnly, secure, and the url-fallback parameter
all round-trip correctly.

Network and Storage cookie handlers share a single parse_cdp_cookie /
parse_delete_cookies_params helper to avoid drift.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

* fix(cdp): fall back to default cookie jar, add Network.getAllCookies

Addresses @SGavrl review on PR #170:

- Network.{set,get,delete}Cookie(s)/clearBrowserCookies now resolve the
  cookie jar via a shared helper that prefers the session page's jar and
  falls back to ctx.default_context.cookie_jar when no target has been
  attached. Mirrors how Storage.setCookies already routes when there is
  no session, so Puppeteer/Playwright flows that issue cookie methods
  before Target.attachToTarget no longer hit "No page".
- Add Network.getAllCookies (separate CDP method per spec); aliases the
  existing getCookies handler so both arms return the full jar.

Tests: 6 new #[tokio::test] cases in domains::network::tests cover the
no-session fallback for set/get/setMany/delete/clear and the new
getAllCookies arm. RED on prod-reverted file (6/6 fail with "No page" /
"Unknown Network method: getAllCookies"), GREEN on patched
(22 -> 30 obscura-cdp lib tests, obscura-net 22/22 baseline preserved).

crates/obscura-cdp/src/lib.rs

@@ -2,6 +2,7 @@ pub mod server;
 pub mod dispatch;
 pub mod types;
 pub mod domains;
+pub mod cookie_params;
 pub(crate) mod util;
 
 pub use server::{