chore: clean up dead code, fix broken test

- Remove unused methods: append_response_text, clear_response,
  has_pending_function_calls, take_function_calls
- Add #[allow(dead_code)] for intentionally kept future-use methods
  and response modification helpers
- Remove unused now_unix import from gemini.rs
- Fix test_modify_strips_all_tools: tools key is removed entirely
  when no custom tools provided, not left as empty array
- Zero warnings, 32 tests passing

src/mitm/store.rs

@@ -281,26 +281,6 @@ impl MitmStore {
         self.has_active_function_call.store(false, Ordering::SeqCst);
     }
 
-    /// Check if there are pending function calls for a cascade.
-    pub async fn has_pending_function_calls(&self, cascade_id: &str) -> bool {
-        let pending = self.pending_function_calls.read().await;
-        pending.get(cascade_id).map_or(false, |v| !v.is_empty())
-    }
-
-    /// Take (consume) pending function calls.
-    pub async fn take_function_calls(&self, cascade_id: &str) -> Option<Vec<CapturedFunctionCall>> {
-        let mut pending = self.pending_function_calls.write().await;
-        let calls = pending.remove(cascade_id);
-        let result = if calls.is_none() {
-            pending.remove("_latest")
-        } else {
-            calls
-        };
-        if result.is_some() {
-            self.has_active_function_call.store(false, Ordering::SeqCst);
-        }
-        result
-    }
 
     /// Take any pending function calls (ignoring cascade ID).
     pub async fn take_any_function_calls(&self) -> Option<Vec<CapturedFunctionCall>> {
@@ -381,15 +361,7 @@ impl MitmStore {
 
     // ── Direct response capture (bypass LS) ──────────────────────────────
 
-    /// Append text to the captured response.
-    pub async fn append_response_text(&self, text: &str) {
-        let mut resp = self.captured_response_text.write().await;
-        if let Some(ref mut existing) = *resp {
-            existing.push_str(text);
-        } else {
-            *resp = Some(text.to_string());
-        }
-    }
+
 
     /// Set (replace) the captured response text.
     pub async fn set_response_text(&self, text: &str) {
@@ -416,14 +388,7 @@ impl MitmStore {
         self.response_complete.load(Ordering::SeqCst)
     }
 
-    /// Clear captured response state (call at start of new request).
-    pub fn clear_response(&self) {
-        self.response_complete.store(false, Ordering::SeqCst);
-        // Can't use async in sync fn, so we spawn a task... or just use try_write
-        if let Ok(mut resp) = self.captured_response_text.try_write() {
-            *resp = None;
-        }
-    }
+
 
     /// Async version of clear_response.
     pub async fn clear_response_async(&self) {
@@ -458,11 +423,13 @@ impl MitmStore {
     }
 
     /// Get the active cascade ID.
+    #[allow(dead_code)]
     pub async fn get_active_cascade(&self) -> Option<String> {
         self.active_cascade_id.read().await.clone()
     }
 
     /// Clear the active cascade ID (called after response is complete).
+    #[allow(dead_code)]
     pub async fn clear_active_cascade(&self) {
         *self.active_cascade_id.write().await = None;
     }