add(test): test execution into zterm test build

src/terminal.zig

@@ -205,3 +205,7 @@ fn getReportMode(ps: u8) ReportMode {
         else => ReportMode.not_recognized,
     };
 }
+
+test {
+    _ = @import("terminal/style.zig");
+}

src/terminal/style.zig

@@ -283,3 +283,7 @@ pub fn value(this: @This(), writer: anytype, content: []const u8) !void {
 // TODO: implement helper functions for terminal capabilities:
 // - links / url display (osc 8)
 // - show / hide cursor?
+
+test {
+    _ = Color;
+}

src/zterm.zig

@@ -8,5 +8,6 @@ pub const Key = terminal.Key;
 pub const Size = terminal.Size;
 
 test {
+    _ = @import("terminal.zig");
     _ = @import("queue.zig");
 }