feat: group multi-browser output by source

- Add browser source grouping metadata to SDK-created tabs, groups,
  list results, and aggregate count results.
- Render grouped local/remote browser tables consistently for clients,
  tabs, groups, windows, sessions, and remote status output.
- Document remote control, auth, HTTP gateway usage, and the refreshed
  project structure in the README.
- Add coverage for grouped output and BrowserCounts browser_groups.
- Bump the Python package, extension manifest, and lockfile to 0.15.6.
- Add a just publish helper for building and publishing release artifacts.

browser_cli/commands/groups.py

@@ -1,33 +1,19 @@
 import click
 from browser_cli.commands import client_from_ctx, gentle_mode_option, handle_errors, print_counts
+from browser_cli.commands.rendering import print_browser_grouped_table_rows
 from rich.console import Console
-from rich.table import Table
 
 console = Console()
 
 def _print_groups(groups, *, show_browser: bool = False) -> None:
-    if not groups:
-        console.print("[yellow]No groups found[/yellow]")
-        return
-    table = Table(show_header=True, header_style="bold cyan")
-    if show_browser:
-        table.add_column("Browser")
-    table.add_column("ID", style="dim", no_wrap=True)
-    table.add_column("Name")
-    table.add_column("Color", width=10)
-    table.add_column("Collapsed", width=10)
-    table.add_column("Tabs", width=6)
-    for g in groups:
-        row = [
-            (g.browser or "") if show_browser else None,
-            str(g.id),
-            g.title or "",
-            g.color or "",
-            "yes" if g.collapsed else "no",
-            str(g.tab_count),
-        ]
-        table.add_row(*[value for value in row if value is not None])
-    console.print(table)
+    columns = [
+        ("ID", lambda g: g.id),
+        ("Name", lambda g: g.title or ""),
+        ("Color", lambda g: g.color or ""),
+        ("Collapsed", lambda g: "yes" if g.collapsed else "no"),
+        ("Tabs", lambda g: g.tab_count),
+    ]
+    print_browser_grouped_table_rows(groups, columns, console=console, empty_message="[yellow]No groups found[/yellow]")
 
 @click.group("groups")
 def group_group():