Implement breakpointObserver.

Drop breakpoints constant export from Breakpoint component.
Expose breakpoints constant separately and freeze it.
Change `match` event to 'change`, because it is now based on store and captures initial value change.

Issues:
- Wrong exports in types/index.d.ts
- Typedefs lost from docs.

types/Breakpoint/Breakpoint.svelte.d.ts

@@ -1,10 +1,6 @@
 /// <reference types="svelte" />
 import { SvelteComponentTyped } from "svelte";
 
-export type BreakpointSize = "sm" | "md" | "lg" | "xlg" | "max";
-
-export type BreakpointValue = 320 | 672 | 1056 | 1312 | 1584;
-
 export interface BreakpointProps {
   /**
    * Determine the current Carbon grid breakpoint size
@@ -22,15 +18,10 @@ export interface BreakpointProps {
 export default class Breakpoint extends SvelteComponentTyped<
   BreakpointProps,
   {
-    match: CustomEvent<{
+    change: CustomEvent<{
       size: BreakpointSize;
       breakpointValue: BreakpointValue;
     }>;
   },
   { default: { size: BreakpointSize; sizes: Record<BreakpointSize, boolean> } }
-> {
-  /**
-   * Reference the Carbon grid breakpoints
-   */
-  breakpoints: Record<BreakpointSize, BreakpointValue>;
-}
+> {}