Update docs generators to include proper edit on github links

Ref: https://github.com/ghostty-org/website/pull/197

src/build/webgen/main_actions.zig

@@ -13,6 +13,7 @@ pub fn genKeybindActions(writer: anytype) !void {
         \\---
         \\title: Keybinding Action Reference
         \\description: Reference of all Ghostty keybinding actions.
+        \\editOnGithubLink: https://github.com/ghostty-org/ghostty/edit/main/src/input/Binding.zig
         \\---
         \\
         \\This is a reference of all Ghostty keybinding actions.

src/build/webgen/main_config.zig

@@ -13,6 +13,7 @@ pub fn genConfig(writer: anytype) !void {
         \\---
         \\title: Reference
         \\description: Reference of all Ghostty configuration options.
+        \\editOnGithubLink: https://github.com/ghostty-org/ghostty/edit/main/src/config/Config.zig
         \\---
         \\
         \\This is a reference of all Ghostty configuration options. These