chore: document some interfaces (#52)

This would've helped me when getting started with this repo

Author: dummdidumm

types.d.ts

@@ -8,41 +8,74 @@ export interface EnvironmentData {
 }
 
 export interface RunOptions {
+	/** Workspace package name to run. */
 	workspace: string
+	/** Repository root directory. */
 	root: string
+	/** Local path to the Svelte package. */
 	sveltePath: string
+	/** Installed Svelte major version. */
 	svelteMajor: number
+	/** Enable extra verification checks. */
 	verify?: boolean
+	/** Skip git clone/fetch steps. */
 	skipGit?: boolean
+	/** Release channel/version to test against. */
 	release?: string
+	/** Preferred package manager. */
 	agent?: (typeof AGENTS)[number]
+	/** Build task(s) to run; skipped when omitted. */
 	build?: Task | Task[]
+	/** Test task(s) to run; skipped when omitted. */
 	test?: Task | Task[]
+	/** Task(s) to run before installing dependencies. */
 	beforeInstall?: Task | Task[]
+	/** Task(s) to run before build. */
 	beforeBuild?: Task | Task[]
+	/** Task(s) to run before test. */
 	beforeTest?: Task | Task[]
 }
 
 type Task = string | { script: string; args?: string[] } | (() => Promise<any>)
 
 export interface CommandOptions {
+	/** Suites to include; runs all when omitted. */
 	suites?: string[]
+	/** Repository in owner/name format. */
 	repo?: string
+	/** Git branch to use. */
 	branch?: string
+	/** Git tag to use. */
 	tag?: string
+	/** Git commit SHA to use. */
 	commit?: string
+	/** Release channel/version override. */
 	release?: string
+	/** Enable verification checks. */
 	verify?: boolean
+	/** Skip git operations. */
 	skipGit?: boolean
 }
 
 export interface RepoOptions {
+	/** Repository in owner/name format. */
 	repo: string
+	/** Target directory name for checkout. */
 	dir?: string
+	/** Git branch to checkout. */
 	branch?: string
+	/** Git tag to checkout. */
 	tag?: string
+	/** Git commit SHA to checkout. */
 	commit?: string
+	/** Perform a shallow clone. */
 	shallow?: boolean
+	/**
+	 * Key is the dependency, value is one of:
+	 * - `string`: override dependency source/version (local paths are supported).
+	 * - `true`: force-build and override this package from local builds.
+	 * - `false`: disable a previously set boolean flag.
+	 */
 	overrides?: Overrides
 }