feat: add bsk network read-only command

Add `bsk network` as a sibling of the `console` command from #7,
reading the buffered network responses / failures for a tab. Fills the
remaining half of the request in #2 (console landed in #7; network did
not).

Mirrors the console command's conventions exactly:

  bsk network --session <id> [--tab-id N] [--since C]
                             [--limit N] [--max-text-chars N]

The extension enables `Network` on attach (best-effort) and buffers
`responseReceived` / `loadingFailed` events per tab with a monotonic
sequence, correlating them to `requestWillBeSent` for method/URL. Reads
are cursor-paginated (`since` -> `next_since`) and bounded (`limit`,
`max_text_chars`) for agent-context safety, same as console. Entries
carry the real HTTP status code (response) or the CDP failure reason
(failure) — things `performance.getEntriesByType('resource')` can't
give.

Classified read-only (pass-through under the pending-interrupt gate);
defaults to the Agent Window's active tab.

Wires bsk-protocol (Method + params/result/entry structs + schema),
bsk-cli (network subcommand + daemon dispatch allow-list) and the
extension (handler + dispatcher route), with unit / parse / IPC tests
paralleling the console command.

Refs #2.

crates/bsk-protocol/src/method.rs

@@ -64,6 +64,8 @@ pub enum Method {
     ToolScreenshot,
     #[serde(rename = "tool.console")]
     ToolConsole,
+    #[serde(rename = "tool.network")]
+    ToolNetwork,
     #[serde(rename = "tool.evaluate")]
     ToolEvaluate,
     #[serde(rename = "tool.wait_for_navigation")]
@@ -127,6 +129,7 @@ impl Method {
             | Method::ToolGetHtml
             | Method::ToolScreenshot
             | Method::ToolConsole
+            | Method::ToolNetwork
             | Method::ToolWaitForNavigation
             | Method::ToolWaitMs
             | Method::ToolRequestHelp => false,
@@ -169,6 +172,13 @@ mod tests {
         assert_eq!(serde_json::to_value(method).unwrap(), json!("tool.console"));
     }
 
+    #[test]
+    fn network_method_round_trips() {
+        let method: Method = serde_json::from_value(json!("tool.network")).unwrap();
+        assert_eq!(method, Method::ToolNetwork);
+        assert_eq!(serde_json::to_value(method).unwrap(), json!("tool.network"));
+    }
+
     #[test]
     fn cancel_params_and_result_round_trip() {
         let params: CancelParams = serde_json::from_value(json!({ "rpc_id": "wait-1" })).unwrap();
@@ -187,6 +197,7 @@ mod tests {
         assert!(!Method::ToolGetHtml.is_mutating());
         assert!(!Method::ToolScreenshot.is_mutating());
         assert!(!Method::ToolConsole.is_mutating());
+        assert!(!Method::ToolNetwork.is_mutating());
         assert!(!Method::ToolWaitForNavigation.is_mutating());
         assert!(!Method::ToolWaitMs.is_mutating());
     }