unicode: isolate properties, tables, and ziglyph into separate files

This makes it cleaner to add new sources of table generation and also
avoids inadvertently depending on different modules (despite Zig's lazy
analysis). 

This also fixes up terminal to only use our look up tables which avoids
bringing ziglyph in for the terminal module.

src/unicode/props_table.zig

@@ -0,0 +1,18 @@
+const Properties = @import("Properties.zig");
+const lut = @import("lut.zig");
+
+/// The lookup tables for Ghostty.
+pub const table = table: {
+    // This is only available after running a generator as part of the Ghostty
+    // build.zig process, but due to Zig's lazy analysis we can still reference
+    // it here.
+    //
+    // An example process is the `main` in `props_ziglyph.zig`
+    const generated = @import("unicode_tables").Tables(Properties);
+    const Tables = lut.Tables(Properties);
+    break :table Tables{
+        .stage1 = &generated.stage1,
+        .stage2 = &generated.stage2,
+        .stage3 = &generated.stage3,
+    };
+};