Correct typographic styles

• Corrected typographic styles ( T377558)
• Set proper style for the Edit button ( T378027)
• Iconography was updated ( T377819)
• machine-readable name and stream name (when app/base schema is selected) are set as readonly instead of disabled ( T377817)
• Set the right background color for dark mode ( T377603)

Also some other minor issues:

• Fixed the issue that disabled any instrument/experiment after being modified
• Took the opportunity to organize Vue parts. The right order is script, template and style
• cdx-lookup component for selecting stream name was broken. v-initial-input-value was deprecated at some point in favour of input-value (a couple more occurrences have been fixed)
• Some placeholders have been added
• sampling unit select component is part of Sampling.vue (it was placed at the beginning of the Specifications.vue file)

Closes T377558, T378027, T377819, T377817, T377603