Add get_all_accounts() method to FavaClient for account sync

fava_client.py

@@ -816,6 +816,49 @@ class FavaClient:
             limit=limit
         )
 
+    async def get_all_accounts(self) -> List[Dict[str, Any]]:
+        """
+        Get all accounts from Beancount/Fava.
+
+        Returns:
+            List of account dictionaries:
+                [
+                    {"account": "Assets:Cash", "meta": {...}},
+                    {"account": "Expenses:Food", "meta": {...}},
+                    ...
+                ]
+
+        Example:
+            accounts = await fava.get_all_accounts()
+            for acc in accounts:
+                print(acc["account"])  # "Assets:Cash"
+        """
+        try:
+            # Use Fava's /api/accounts endpoint
+            async with httpx.AsyncClient(timeout=self.timeout) as client:
+                response = await client.get(f"{self.base_url}/api/accounts")
+                response.raise_for_status()
+                accounts_data = response.json()
+
+                # Fava returns array of account names
+                # We need to convert to dict format expected by account_sync
+                accounts = []
+                for acc_name in accounts_data:
+                    accounts.append({
+                        "account": acc_name,
+                        "meta": {}  # Fava /api/accounts doesn't include metadata
+                    })
+
+                logger.debug(f"Fava returned {len(accounts)} accounts")
+                return accounts
+
+        except httpx.HTTPStatusError as e:
+            logger.error(f"Fava accounts error: {e.response.status_code} - {e.response.text}")
+            raise
+        except httpx.RequestError as e:
+            logger.error(f"Fava connection error: {e}")
+            raise
+
     async def get_journal_entries(self) -> List[Dict[str, Any]]:
         """
         Get all journal entries from Fava (with entry hashes).