fix(prometheus, syslog): a target or pattern pauses with a Pause/Resume button, not an "on" tick box in its form (#6419)

Monitors, schedules and maintenance plans already pause with a
Pause/Resume button and say "Paused" where they're listed. Prometheus
targets and syslog patterns only had a tick box inside the edit form,
so a target refused by its endpoint couldn't be stopped from its page.

- Both get a Pause/Resume button (target page and list; patterns list)
  posting to /toggle, recorded in the audit log, and a Paused badge.
- The forms lose the tick box. A new one starts running; an edit keeps
  whether it is paused.
- A target's "off" state is now "paused", in its pages and MCP tools.
  A resumed target reads "not scraped yet" until its next scrape, and its
  counter rates start over.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

plugins/syslog/patterns.py

@@ -108,8 +108,7 @@ def parse_form(form) -> dict:
     if window not in WINDOWS:
         window = 15
     return {"name": name, "phrases": phrases, "max_severity": max_severity,
-            "source_id": form.get("source_id") or None, "window_minutes": window,
-            "enabled": "enabled" in form}
+            "source_id": form.get("source_id") or None, "window_minutes": window}
 
 
 def matches(pattern, severity: int, message: str) -> bool: