Added disabled spoken forms error (#2509)

## Checklist

- [/] I have added
[tests](https://www.cursorless.org/docs/contributing/test-case-recorder/)
- [/] I have updated the
[docs](https://github.com/cursorless-dev/cursorless/tree/main/docs) and
[cheatsheet](https://github.com/cursorless-dev/cursorless/tree/main/cursorless-talon/src/cheatsheet)
- [/] I have not broken the cheatsheet

---------

Co-authored-by: Pokey Rule <755842+pokey@users.noreply.github.com>

Author: AndreasArvidsson

packages/common/src/types/TalonSpokenForms.ts

@@ -42,3 +42,10 @@ export class NeedsInitialTalonUpdateError extends Error {
     this.name = "NeedsInitialTalonUpdateError";
   }
 }
+
+export class DisabledCustomSpokenFormsError extends Error {
+  constructor() {
+    super("Custom spoken forms are not currently supported in this ide");
+    this.name = "DisabledCustomSpokenFormsError";
+  }
+}

packages/cursorless-engine/src/disabledComponents/DisabledTalonSpokenForms.ts

@@ -1,8 +1,12 @@
-import type { SpokenFormEntry, TalonSpokenForms } from "@cursorless/common";
+import {
+  DisabledCustomSpokenFormsError,
+  type SpokenFormEntry,
+  type TalonSpokenForms,
+} from "@cursorless/common";
 
 export class DisabledTalonSpokenForms implements TalonSpokenForms {
   getSpokenFormEntries(): Promise<SpokenFormEntry[]> {
-    throw Error("Talon spoken forms are not implemented.");
+    throw new DisabledCustomSpokenFormsError();
   }
 
   onDidChange() {

packages/cursorless-engine/src/spokenForms/CustomSpokenForms.ts

@@ -1,5 +1,6 @@
 import {
   CustomRegexScopeType,
+  DisabledCustomSpokenFormsError,
   Disposable,
   NeedsInitialTalonUpdateError,
   Notifier,
@@ -81,6 +82,8 @@ export class CustomSpokenForms {
       if (err instanceof NeedsInitialTalonUpdateError) {
         // Handle case where spokenForms.json doesn't exist yet
         this.needsInitialTalonUpdate_ = true;
+      } else if (err instanceof DisabledCustomSpokenFormsError) {
+        // Do nothing: this ide doesn't currently support custom spoken forms
       } else {
         console.error("Error loading custom spoken forms", err);
         const msg = (err as Error).message.replace(/\.$/, "");