refactor(docs): Convert the keymaps section into a base folder (#2430)

Co-authored-by: Cem Aksoylar <caksoylar@users.noreply.github.com>

docs/docs/keymaps/behaviors/mod-tap.md

@@ -0,0 +1,54 @@
+---
+title: Mod-Tap Behavior
+sidebar_label: Mod-Tap
+---
+
+## Summary
+
+The Mod-Tap behavior sends a different keypress, depending on whether it's held or tapped.
+
+- If you hold the key for longer than 200ms, the first keycode ("mod") is sent.
+- If you tap the key (release before 200ms), the second keycode ("tap") is sent.
+
+If you press another key within the 200ms, the 'mod' behavior is also activated.
+
+## Mod-Tap
+
+The Mod-Tap behavior either acts as a held modifier, or as a tapped keycode.
+
+### Behavior Binding
+
+- Reference: `&mt`
+- Parameter #1: The keycode to be sent when activating as a modifier, e.g. `LSHIFT`
+- Parameter #2: The keycode to sent when used as a tap, e.g. `A`, `B`.
+
+Example:
+
+```dts
+&mt LSHIFT A
+```
+
+### Configuration
+
+You can configure a different tapping term in your keymap:
+
+```dts
+&mt {
+    tapping-term-ms = <400>;
+};
+
+/ {
+    keymap {
+        ...
+    };
+};
+```
+
+:::info
+Under the hood, the mod-tap is simply a [hold-tap](hold-tap.mdx) of the ["hold-preferred" flavor](hold-tap.mdx#flavors) with a [`tapping-term-ms`](hold-tap.mdx#tapping-term-ms) of 200 that takes in two [keypresses](key-press.md) as its "hold" and "tap" parameters. This means that the mod-tap can be used to invoke **any** [keycode](../list-of-keycodes.mdx), and is not limited to only activating [modifier keys](../modifiers.mdx) when it is held.
+
+For users who want to momentarily access a specific [layer](../index.mdx#layers) while a key is held and send a keycode when the same key is tapped, see [Layer-Tap](layers.md#layer-tap).
+
+Similarly, for users looking to create a keybind like the mod-tap that invokes behaviors _other_ than [keypresses](key-press.md), like [sticky keys](sticky-key.md) or [key toggles](key-toggle.md), see [Hold-Tap](hold-tap.mdx).
+
+:::