feat, introduce "local-only" feature to keep components locally for local debugging/test purposes

[davidfirst]

Proposed Changes

• mark components as local-only by bit local-only set <pattern> (undo by local-only unset, list by local-only list).
• these local-only components are excluded from snap/tag/export commands. (unless --include-local-only was used for snap/tag).
• all other commands work as normal for these local-only components.
• bit status shows a new section "local only components".
• added a new state-filter $localOnly. Can be used for all commands that support pattern.

Edit: some specs have changed in a later PR: https://github.com/teambit/bit/pull/9059