fetch market data symbols concurrently instead of sequentially

fetch_market_data hit Yahoo's v8 chart endpoint once per symbol in a
sequential loop — with 9 symbols that's 9 round trips end to end.
join_all fires them together.

src-tauri/Cargo.lock

@@ -1094,6 +1094,21 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "futures"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b147ee9d1f6d097cef9ce628cd2ee62288d963e16fb287bd9286455b241382d"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
 [[package]]
 name = "futures-channel"
 version = "0.3.32"
@@ -1101,6 +1116,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "07bbe89c50d7a535e539b8c17bc0b49bdb77747034daa8087407d655f3f7cc1d"
 dependencies = [
  "futures-core",
+ "futures-sink",
 ]
 
 [[package]]
@@ -1168,6 +1184,7 @@ version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "389ca41296e6190b48053de0321d02a77f32f8a5d2461dd38762c0593805c6d6"
 dependencies = [
+ "futures-channel",
  "futures-core",
  "futures-io",
  "futures-macro",
@@ -3710,6 +3727,7 @@ name = "summarum"
 version = "1.2.0"
 dependencies = [
  "chrono",
+ "futures",
  "reqwest 0.12.28",
  "serde",
  "serde_json",

src-tauri/Cargo.toml

@@ -20,6 +20,7 @@ serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 reqwest = { version = "0.12", default-features = false, features = ["json", "rustls-tls"] }
 chrono = "0.4"
+futures = "0.3.32"
 
 [profile.release]
 strip = true

src-tauri/src/main.rs

@@ -295,23 +295,32 @@ async fn fetch_market_data(
     // v7/finance/quote now requires a cookie+crumb pair Yahoo stopped issuing
     // to plain API clients (returns 401); v8 chart still answers anonymously,
     // one symbol per request.
-    let mut prices = std::collections::HashMap::new();
-    for sym in &symbols {
-        let url = format!(
-            "https://query1.finance.yahoo.com/v8/finance/chart/{}?range=1d&interval=1d",
-            sym
-        );
-        let Ok(resp) = client.get(&url).send().await else {
-            continue;
-        };
-        let Ok(body) = resp.json::<serde_json::Value>().await else {
-            continue;
-        };
-        if let Some(price) = body["chart"]["result"][0]["meta"]["regularMarketPrice"].as_f64() {
-            if price > 0.0 {
-                prices.insert(sym.clone(), price);
+    let futures_reqs = symbols.iter().map(|sym| {
+        let client = client.clone();
+        async move {
+            let url = format!(
+                "https://query1.finance.yahoo.com/v8/finance/chart/{}?range=1d&interval=1d",
+                sym
+            );
+            if let Ok(resp) = client.get(&url).send().await {
+                if let Ok(body) = resp.json::<serde_json::Value>().await {
+                    if let Some(price) =
+                        body["chart"]["result"][0]["meta"]["regularMarketPrice"].as_f64()
+                    {
+                        if price > 0.0 {
+                            return Some((sym.clone(), price));
+                        }
+                    }
+                }
             }
+            None
         }
+    });
+
+    let mut prices = std::collections::HashMap::new();
+    let results = futures::future::join_all(futures_reqs).await;
+    for (sym, price) in results.into_iter().flatten() {
+        prices.insert(sym, price);
     }
 
     if !prices.is_empty() {