Restructure data editor messaging with Message Registry

[stricklandrbls]

Closes #1058
Closes #669

Description

• Implemented a Message Registry which provides type-safe message content inspection for messages sent between the data editor, dfdl extension, and the Svelte UI.
• Restructured some legacy Svelte stores into Svelte v5 runes.
• Resolved issues related to message content mismathcing and message content being processed by multiple data editors when the message was intended for a single data editor instance.

Wiki

• I have determined that no documentation updates are needed for these changes
• I have added the following documentation for these changes

Review Instructions including Screenshots

Developer Perspective Reviews

1. In any portion of the data editor's extension source, verify that message content is appropriately inspected and the VSCode intellisense engine emits correct types when invoking this.panel.postMessage(...).

Screenshots ( dataEditorClient.ts -> 'fileInfo')

2. In any portion of the data editor's Svelte UI source, verify that message content is appropriately inspected and the VSCode intellisense engine emits correct types when invoking addListener(...).

Screenshots ( DataEditorLineFeed.svelte -> 'viewportRefresh')

3. In any portion of the data editor's Svelte UI source, verify that message content is appropriately inspected and the VSCode intellisense engine emits correct types when invoking vscode.postMessage(...).

Screenshots ( App.svelte -> 'requestEditedData')

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Functionality Review

Verify that all message traffic behaves as expected. Message content can be identified within the ./src/ext_types/message.ts & ./src/ext_types/messageContent.ts

[CoverRyan]

CI seems to be failing consistently and it doesn't appear to be an issue with the CI.

[stricklandrbls]

CI seems to be failing consistently and it doesn't appear to be an issue with the CI.

#1659 is the issue I created for fixing the CI

[shanedell]

@stricklandrbls Will the updates to fix #1659 be added to this PR? My personal input would be, to add those changes here. I would rather have additional changes in this PR and a working CI then to merge this PR and introduce broken CI into main which requires another PR to fix.

[stricklandrbls]

@stricklandrbls Will the updates to fix #1659 be added to this PR? My personal input would be, to add those changes here. I would rather have additional changes in this PR and a working CI then to merge this PR and introduce broken CI into main which requires another PR to fix.

Yeah those changes would fix the CI I created the separate issue because it required multiple additional dev dependencies.

I can add that issue as one that will close this PR.