Standardizing syntax and discouraging use of `this` inside tests

[StandaloneEditor] Initialize static field 'SCHEME'

Simplify terminal ID retry mechanism

This reverts commit f25e9c10.

Reverts #59089

After further discussions with the team, we decided that we should not ship a bundled toml grammar. There are two reasons for this:

* For the best toml experiance, users should use one of the toml plugins from the marketplace as these provide intellisense and other advanced language features. We previously recommend these plugins when you opened a toml file. However if we ship a bundled toml grammar, these recommendations will no longer appear

* Engineering maintance costs on our side. Updating the grammar, maintaining tests, and handling issues related to it are all extra work that has to be considered.

For these reasons, we do not think it makes sense to include basic toml support

Fixes #59765

Adding todo about addressing this

Fixes #59757

This reverts commit 8f20c5ea.

Implemented prefilling quickOpen with last search input.

Includes link overscan fix and dynamic cache optimizations