[wiki migration] Tool team pages (#148779)

This puts the wiki pages owned by the Tool team into the docs/tool directory as planned in [flutter.dev/go/migrate-flutter-wiki-spreadsheet](https://docs.google.com/spreadsheets/d/1x65189ZBdNiLRygpUYoU08pwvXD4M-Z157c6pm8deGI/edit?usp=sharing) 

It also adds the tool team labels to the label bot for future PRs.

Changes to the content were only updating cross links, or link to refer to the main branch rather than master.
Remaining links to the wiki will be updated once all other pages have finished moving, they still work in the meantime.

Part of https://github.com/flutter/flutter/issues/145009

.github/labeler.yml

@@ -188,8 +188,14 @@ team-release:
     - any-glob-to-any-file:
       - docs/releases/**/*
 
+team-tool:
+  - changed-files:
+    - any-glob-to-any-file:
+      - docs/tool/**/*
+
 tool:
   - changed-files:
     - any-glob-to-any-file:
       - packages/flutter_tools/**/*
       - packages/fuchsia_remote_debug_protocol/**/*
+      - docs/tool/**/*