feat: Stockbit login for the order book, live quotes and daily history

Opt-in, with the user's own Stockbit session from a pasted
credentialStorage cookie (or IDX_STOCKBIT_REFRESH_TOKEN):

- idx stockbit login/status/logout; session file 0600, tokens never shown
- rotating refresh under a cross-process lock; one refresh+retry on 401
- stocks orderbook: depth with lots and orders, OHLC, value, foreign flow
- --provider stockbit quotes from the session API when logged in
- --history-provider stockbit, and auto under the stockbit provider for
  5d-1y daily windows
- MCP get_orderbook and stockbit_status (17 tools)

Endpoints, units and recorded responses from fzn0x/idx (MIT).

crates/idx-mcp/src/params.rs

@@ -38,6 +38,15 @@ pub struct IntradayParams {
     pub tail: Option<usize>,
 }
 
+#[derive(Debug, Deserialize, JsonSchema)]
+pub struct OrderBookParams {
+    /// IDX ticker, e.g. "BBCA".
+    pub symbol: String,
+    /// Price levels per side (default 10, at most 50).
+    #[serde(default)]
+    pub depth: Option<usize>,
+}
+
 #[derive(Debug, Deserialize, JsonSchema)]
 pub struct ScreenParams {
     /// Screen to run (default "top-performers").