[DOCS] Edit the Watcher summaries and descriptions

[lcawl]

Relates to #3226

This PR edits the Watcher APIs (https://www.elastic.co/docs/api/doc/elasticsearch/group/endpoint-watcher) based on the information in https://www.elastic.co/guide/en/elasticsearch/reference/master/watcher-api.html

It also adds a link and description to the "Watcher" tag and edits some of the other tag links for consistency.

[github-actions]

Following you can find the validation results for the APIs you have changed.

API	Status	Request	Response
watcher.ack_watch	🟢	1/1	1/1
watcher.activate_watch	🟢	1/1	1/1
watcher.deactivate_watch	🟢	1/1	1/1
watcher.delete_watch	🟢	2/2	2/2
watcher.execute_watch	🟢	7/7	7/7
watcher.get_watch	🟢	9/9	9/9
watcher.put_watch	🔴	29/38	38/38
watcher.query_watches	⚪	Missing test	Missing test
watcher.start	🟢	1/1	1/1
watcher.stats	🟢	1/1	1/1
watcher.stop	🟢	1/1	1/1

You can validate these APIs yourself by using the make validate target.

[kilfoyle]

LGTM! 🐰

[github-actions]

The backport to 8.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-8.x 8.x
# Navigate to the new working tree
cd .worktrees/backport-8.x
# Create a new branch
git switch --create backport-3345-to-8.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 f6c1c74a558ebd32769a8535d59fa5fa148cbe25
# Push it to GitHub
git push --set-upstream origin backport-3345-to-8.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-8.x

Then, create a pull request where the base branch is 8.x and the compare/head branch is backport-3345-to-8.x.

[github-actions]

The backport to 8.17 failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-8.17 8.17
# Navigate to the new working tree
cd .worktrees/backport-8.17
# Create a new branch
git switch --create backport-3345-to-8.17
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 f6c1c74a558ebd32769a8535d59fa5fa148cbe25
# Push it to GitHub
git push --set-upstream origin backport-3345-to-8.17
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-8.17

Then, create a pull request where the base branch is 8.17 and the compare/head branch is backport-3345-to-8.17.

[lcawl]

💚 All backports created successfully

Status	Branch	Result
✅	8.x

Questions ?

Please refer to the Backport tool documentation

[lcawl]

💚 All backports created successfully

Status	Branch	Result
✅	8.17

Questions ?

Please refer to the Backport tool documentation