feat: cookie jar persistence + --storage-dir flag + fix HTTP cookie header filtering (#114)

* feat: cookie jar persistence + storage-dir + filtering fix (clean v4)

* fix: resolve build errors, add storage_dir param throughout server chain

* fix: storage_dir end-to-end, plus two test-literal field additions

  Five issues found while testing PR 114 end-to-end.

  Build fixes (two test literals out of sync with new struct fields):
  - crates/obscura-net/src/cookies.rs: CookieInfo literal in
    test_domain_matches_subdomain_without_leading_dot was missing the
    same_site and expires fields added in #170.
  - crates/obscura-cli/src/main.rs: Command::Fetch literal in
    matcher_still_uses_fetch_variant was missing the new storage_dir
    field. Without these cargo test --workspace would not compile.

  run_fetch was branching between BrowserContext::with_storage (which
  hardcodes proxy=None, stealth=false, user_agent=None) and
  with_options (which has no storage_dir slot), so --storage-dir +
  --proxy + --stealth silently dropped the proxy and stealth flags.
  Same bug SGavrl flagged on dispatch.rs in the previous round, just on
  the other code path. Switched to with_storage_full which carries all
  four. Verified the fetch now errors out against an invalid proxy.

  run_fetch --eval short-circuited the function before
  context.save_cookies() ran, so cookies set during an eval session
  were never persisted to {storage_dir}/cookies.json. Moved the save
  above the return.

  obscura serve loaded cookies on startup but never saved them
  anywhere, so a session that set cookies via Network.setCookie or
  navigation dropped them on shutdown. Subscribed to Ctrl-C once in
  put a single save_cookies() after the loop so both the Ctrl-C path
  and the channel-closed path persist cookies. Verified end-to-end.

---------

Co-authored-by: zhangyang-crazy-one <[email protected]>
Co-authored-by: SGavrl <[email protected]>

crates/obscura-net/src/client.rs

@@ -346,9 +346,33 @@ impl ObscuraHttpClient {
             );
 
             let cookie_header = self.cookie_jar.get_cookie_header(&current_url);
+            tracing::debug!(
+                "Cookie header for {}: {} cookies ({} bytes)",
+                current_url.host_str().unwrap_or("?"),
+                cookie_header.split("; ").filter(|s| !s.is_empty()).count(),
+                cookie_header.len(),
+            );
             if !cookie_header.is_empty() {
-                if let Ok(val) = HeaderValue::from_str(&cookie_header) {
-                    headers.insert(reqwest::header::COOKIE, val);
+                match HeaderValue::from_str(&cookie_header) {
+                    Ok(val) => {
+                        headers.insert(reqwest::header::COOKIE, val);
+                    }
+                    Err(_) => {
+                        let filtered: String = cookie_header
+                            .split("; ")
+                            .filter(|pair| HeaderValue::from_str(pair).is_ok())
+                            .collect::<Vec<_>>()
+                            .join("; ");
+                        if !filtered.is_empty() {
+                            if let Ok(val) = HeaderValue::from_str(&filtered) {
+                                headers.insert(reqwest::header::COOKIE, val);
+                            }
+                        }
+                        tracing::debug!(
+                            "Cookie header invalid chars, filtered {} -> {} bytes",
+                            cookie_header.len(), filtered.len(),
+                        );
+                    }
                 }
             }