perf: concurrent schema fetch, memoize highlighting, cap tables

TablePro/Core/Autocomplete/SQLSchemaProvider.swift

@@ -164,7 +164,8 @@ actor SQLSchemaProvider {
         guard !tables.isEmpty, let connection = connectionInfo else { return nil }
 
         var columnsByTable: [String: [ColumnInfo]] = [:]
-        for table in tables {
+        let tablesToFetch = Array(tables.prefix(settings.maxSchemaTables))
+        for table in tablesToFetch {
             let columns = await getColumns(for: table.name)
             if !columns.isEmpty {
                 columnsByTable[table.name.lowercased()] = columns

TablePro/ViewModels/AIChatViewModel.swift

@@ -445,22 +445,27 @@ final class AIChatViewModel {
         var columns: [String: [ColumnInfo]] = [:]
         var foreignKeys: [String: [ForeignKeyInfo]] = [:]
 
-        for table in tablesToFetch {
-            if let schemaProvider {
-                let cached = await schemaProvider.getColumns(for: table.name)
-                if !cached.isEmpty {
-                    columns[table.name] = cached
+        await withTaskGroup(of: (String, [ColumnInfo]).self) { group in
+            for table in tablesToFetch {
+                group.addTask { [schemaProvider] in
+                    if let schemaProvider {
+                        let cached = await schemaProvider.getColumns(for: table.name)
+                        if !cached.isEmpty {
+                            return (table.name, cached)
+                        }
+                    }
+                    do {
+                        let cols = try await driver.fetchColumns(table: table.name)
+                        return (table.name, cols)
+                    } catch {
+                        Self.logger.debug("Schema context: failed to fetch columns for '\(table.name)'")
+                        return (table.name, [])
+                    }
                 }
             }
-
-            if columns[table.name] == nil {
-                do {
-                    let cols = try await driver.fetchColumns(table: table.name)
-                    columns[table.name] = cols
-                } catch {
-                    Self.logger.warning(
-                        "Failed to fetch columns for table '\(table.name)': \(error.localizedDescription)"
-                    )
+            for await (tableName, cols) in group {
+                if !cols.isEmpty {
+                    columns[tableName] = cols
                 }
             }
         }

TablePro/Views/AIChat/AIChatCodeBlockView.swift

@@ -14,6 +14,8 @@ struct AIChatCodeBlockView: View {
     let language: String?
 
     @State private var isCopied: Bool = false
+    @State private var cachedHighlight: AttributedString?
+    @State private var cachedCodeLength: Int = 0
     @FocusedValue(\.commandActions) private var actions
 
     var body: some View {
@@ -76,12 +78,8 @@ struct AIChatCodeBlockView: View {
 
     private var codeContent: some View {
         ScrollView(.horizontal, showsIndicators: false) {
-            if isSQL {
-                Text(highlightedSQL(code))
-                    .textSelection(.enabled)
-                    .padding(10)
-            } else if isMongoDB {
-                Text(highlightedJavaScript(code))
+            if isSQL || isMongoDB {
+                Text(cachedHighlight ?? AttributedString(code))
                     .textSelection(.enabled)
                     .padding(10)
             } else if isRedis {
@@ -96,6 +94,20 @@ struct AIChatCodeBlockView: View {
                     .padding(10)
             }
         }
+        .onAppear {
+            recomputeHighlight()
+        }
+        .onChange(of: code) {
+            let newLen = (code as NSString).length
+            if newLen - cachedCodeLength >= 50 {
+                recomputeHighlight()
+            }
+        }
+    }
+
+    private func recomputeHighlight() {
+        cachedHighlight = isSQL ? highlightedSQL(code) : highlightedJavaScript(code)
+        cachedCodeLength = (code as NSString).length
     }
 
     private var isSQL: Bool {