fix(maestro): tool icon left of diff stat on sidebar meta line

Meta line fragment order was command last, after the blocked-work diff
stat, so the tool icon sat right of the diff count instead of left.
Reorder to duration/detail/command/diff-stat in both web and TUI
sidebars per docs/SIDEBAR.md, and update the contract doc + TUI tests
to match.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

docs/SIDEBAR.md

@@ -37,7 +37,7 @@ itself is not.
 Line 2 reads left to right:
 
 ```
-[<duration>] [<detail>] [<diff stat> | exited] <command>
+[<duration>] [<detail>] <command> [<diff stat> | exited]
 ```
 
 Its minimum content is therefore just the command.
@@ -83,7 +83,7 @@ fragment; it no longer decides whether line 2 exists.
 while an agent-reported state is in force (see Precedence): when the report
 lapses at its TTL or is replaced, the detail goes with it. The detail
 truncates with `…` ahead of the trailing fragments — a long detail never
-pushes `<blocked work>`, `exited`, or `<command>` off the line, and neither
+pushes `<command>`, `<blocked work>`, or `exited` off the line, and neither
 client ever lets it wrap.
 
 `<diff stat>` is the blocked-work breakdown (#83) in diff notation, replacing