Fix Blockly comment text visibility

[Voodoo2man]

What changed

• keep multiline Blockly comment editing working on mobile and desktop
• keep the editor positioned relative to its Blockly container
• force a readable dark SVG text fill for persisted comment text on the yellow comment block

Scope

• Only src-editor/src/Components/blockly-plugins/field-multilineinput/src/field_multilineinput.ts
• No generated admin bundles, package archives, or lockfile changes

Validation

• TypeScript/Vite editor build passed
• Tested in the local test instance on port 8081

[GermanBluefox]

Thank you, saw too late and already implemented