* Provide additional workspace API to add/remove workspace folders (for #35407)

* add/removeFolders => add/removeFolder

* make add/remove folder return a boolean

* use proper service for workspace editing

* workspac => workspace

* do not log promise canceled messages

* show confirm dialog

deco - use correct/overwrite decorations in scm viewlet because the same URI can have multiple decorations

* introduce IRelativePattern and use in extension API

* 💄

* docs

* introduce RelativePattern

* support RelativePattern also for file watcher

* also make findFiles support RelativePattern

* less type conversion

* add GlobPattern type and remove readonly

* make base a string

* fix setter access to RelativePattern

* fix npe when exclude is undefined

* fix findFiles: pattern seems to be matched against workspace always

* 💄

* clarify glob pattern matching

workspace.openTextDocument works incorectly when passing { content?: string; } as argument (fix #34796)

* Workspace folder picker command (for #32936)

* fix test

* make this proper API

Have `workspace.applyEdit` correctly account for model version changes and reply with false if a model was loaded and changed in the meantime

Fix #32235. Functional style formatter. Color range is all float number and remove fromHex, fromHSL methods.