fix: surface terminal failure log when AI suggests no changes

When the LLM returned zero tool calls for a manual task, the UI hung
on the agent's generic "Analysis complete" message while the DB job
row quietly transitioned to failed. No socket event fired into the
job room, no issue comment was posted (manual tasks have no issue),
and the user had nothing to act on.

- groq_service: tell the truth in the activity log when file_changes
  is empty ("no code changes suggested"), instead of the optimistic
  fallback
- pr_service: insert a role=system, type=terminal job_log row on the
  no-changes failure path so the job room receives a real message
  and the UI can render a clear failure state

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: ashokDevs

backend/services/groq_service.py

@@ -342,11 +342,18 @@ def analyze_issue_and_plan_changes(self, issue_title, issue_body, comment_body,
                 }
 
                 if job_id:
+                    if file_changes:
+                        log_content = message.content or "Analysis complete. Suggested changes prepared."
+                    else:
+                        log_content = (
+                            message.content
+                            or "Analysis complete — no code changes suggested."
+                        )
                     db.insert_job_log({
                         'job_id': job_id,
                         'role': 'assistant',
                         'type': 'message',
-                        'content': message.content or "Analysis complete. Suggested changes prepared.",
+                        'content': log_content,
                         'metadata': {'changes_count': len(file_changes)}
                     })
 

backend/services/pr_service.py

@@ -207,12 +207,27 @@ def _execute_ai_task(self, task):
 
         if not file_changes:
             logger.warning("no_file_changes_suggested", issue_number=issue_number)
+            analysis = ai_result.get('analysis') or 'No analysis provided.'
             if issue_number:
                 self.github_service.add_issue_comment(
                     repo,
                     issue_number,
-                    f"ℹ️ **Analysis Complete**\n\nI analyzed the issue but couldn't determine any necessary code changes.\n\n**Analysis:**\n{ai_result.get('analysis')}"
+                    f"ℹ️ **Analysis Complete**\n\nI analyzed the issue but couldn't determine any necessary code changes.\n\n**Analysis:**\n{analysis}"
                 )
+            if job_id:
+                db.insert_job_log({
+                    'job_id': job_id,
+                    'role': 'system',
+                    'type': 'terminal',
+                    'content': (
+                        "❌ **Job failed** — the AI analyzed the request but did not "
+                        "suggest any code changes. This usually means the prompt was "
+                        "too vague, the relevant files weren't in context, or the "
+                        "model decided no change was warranted.\n\n"
+                        f"**Analysis:**\n{analysis}"
+                    ),
+                    'metadata': {'reason': 'no_file_changes'}
+                })
             return {
                 'success': False,
                 'message': 'AI did not suggest any file changes',