add installation guide and enhance introduction for NextFTC

Author: zachwaffle4

src/content/docs/introduction/index.mdx

@@ -1,6 +1,71 @@
 ---
 title: Introduction
 description: What NextFTC is and how to get started.
+next:
+    label: Installation
+    link: introduction/installation
 ---
 
-Content coming soon.
+import { Tabs, TabItem, CardGrid, Card } from '@astrojs/starlight/components'
+
+NextFTC is a command-based library for programming FTC robots, written in Kotlin with full support for Java.
+It's designed to let you write robot code that's expressive, reusable, and easy to reason about,
+without fighting the FTC SDK.
+
+<CardGrid>
+    <Card title="Control" icon="setting">
+        PID, feedforward, motion profiling, and typed geometry and units, usable on their own even outside of an FTC robot.
+    </Card>
+    <Card title="Hardware" icon="random">
+        Lazily-initialized, caching wrappers around motors, servos, sensors, and vision hardware.
+    </Card>
+    <Card title="Robot" icon="puzzle">
+        `NextRobot`, `Mechanism`, and `NextOpMode` tie everything together into a command-based robot.
+    </Card>
+</CardGrid>
+
+## Why NextFTC?
+
+Most FTC teams write robot code as a pile of `if` statements inside a `while (opModeIsActive())` loop.
+NextFTC replaces that with **mechanisms** (your subsystems, like an arm or intake) and **commands**
+(actions those subsystems can perform), and lets you bind them directly to gamepad input:
+
+<Tabs syncKey="language">
+<TabItem label="Kotlin">
+```kotlin
+class Claw : Mechanism {
+    val servo = NextServo("clawServo")
+
+    fun open() = instant { servo.position = 0.2 }
+    fun close() = instant { servo.position = 0.8 }
+}
+```
+</TabItem>
+<TabItem label="Java">
+```java
+public class Claw implements Mechanism {
+    NextServo servo = new NextServo("clawServo");
+
+    public Command open() { return instant(() -> servo.setPosition(0.2)); }
+    public Command close() { return instant(() -> servo.setPosition(0.8)); }
+}
+```
+</TabItem>
+</Tabs>
+
+## Ivy
+
+NextFTC uses the [Ivy library](https://pedropathing.com/docs/ivy) as its underlying commands framework.
+If you already use Ivy, using NextFTC will be easy!
+If you don't, don't worry.
+Many of the concepts translate cleanly from other command frameworks,
+including NextFTC v1.
+
+## Kotlin and Java
+
+NextFTC is written in Kotlin, but Java is treated as a first-class citizen, not an afterthought.
+Every public API is designed to read naturally from Java, and every code sample in these docs is shown in both languages.
+
+## Ready to get started?
+
+Continue to [Installation](/introduction/installation/) to add NextFTC to your robot project.

src/content/docs/introduction/installation.mdx

@@ -0,0 +1,41 @@
+---
+title: Installation
+description: How to install NextFTC libraries.
+prev:
+    label: Introduction
+    link: introduction/index
+---
+
+import { Aside } from '@astrojs/starlight/components'
+
+<Aside type='danger'>
+    Installing NextFTC v2 in a project that already has NextFTC v1 will work,
+    but run into errors at build-time, as the libraries contain classes with the same name.
+
+    It is recommended to remove NextFTC v1 from your project and follow the migration guide (coming soon).
+</Aside>
+
+To install NextFTC in an FTC robot project, open `TeamCode/build.gradle`,
+and add the following to your `dependencies` block:
+
+```groovy
+implementation 'dev.nextftc.v2:control:VERSION'
+implementation 'dev.nextftc.v2:hardware:VERSION'
+implementation 'dev.nextftc.v2:robot:VERSION'
+```
+
+<Aside type='tip' title=''>
+    Replace the `VERSION` with the latest version from Maven Central (omitting the `v` prefix):
+    <img alt="Maven Central Version" src="https://img.shields.io/maven-central/v/dev.nextftc.v2/robot?strategy=highestVersion&style=flat&label=%20Version&labelColor=163650&color=b3d3ec"/>
+</Aside>
+
+Note that the control and hardware modules can be used on their own.
+
+If you are using the hardware and/or robot modules,
+add the following to the `repositories` block to allow Gradle to find the necessary dependencies.
+
+```groovy
+maven {
+    url 'https://repo.dairy.foundation/releases'
+}
+```