digest: record AICall rows so digest LLM spend counts toward monthly cap

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/jobs/email_digest_job.py

@@ -69,9 +69,15 @@ async def _already_sent_today(session, user_id: int, kind: str, today: datetime)
     return (await session.execute(stmt)).first() is not None
 
 
-async def _generate_variants(client, kind: str, ctx: dict) -> dict[str, str]:
+async def _generate_variants(session, client, kind: str, ctx: dict) -> dict[str, str]:
     """Returns {tone: html_content}. Missing tone means generation failed
-    for that variant — skip recipients on that tone."""
+    for that variant — skip recipients on that tone.
+
+    Persists an AICall row per attempt so digest LLM spend counts toward
+    the monthly cost cap on subsequent runs."""
+    from app.models import AICall
+    from app.services.openrouter import active_model
+
     builder = build_weekly_digest_prompt if kind == "weekly" else build_daily_digest_prompt
     out: dict[str, str] = {}
     for tone in ("NOVICE", "INTERMEDIATE"):
@@ -83,10 +89,23 @@ async def _generate_variants(client, kind: str, ctx: dict) -> dict[str, str]:
                  {"role": "user", "content": usr}],
             )
             out[tone] = result.content
+            session.add(AICall(
+                model=result.model,
+                prompt_tokens=result.prompt_tokens,
+                completion_tokens=result.completion_tokens,
+                cost_usd=result.cost_usd,
+                status="ok",
+            ))
+            await session.commit()
             log.info("digest.variant_ok", kind=kind, tone=tone,
                      prompt_tokens=result.prompt_tokens,
                      completion_tokens=result.completion_tokens)
         except Exception as e:
+            session.add(AICall(
+                model=active_model(), status="error",
+                error=f"{kind}/{tone}: {str(e)[:480]}",
+            ))
+            await session.commit()
             log.error("digest.variant_failed", kind=kind, tone=tone,
                       error=str(e)[:200])
     return out
@@ -173,7 +192,7 @@ async def run() -> None:
         )
 
         async with httpx.AsyncClient(follow_redirects=True) as client:
-            variants = await _generate_variants(client, kind, ctx)
+            variants = await _generate_variants(session, client, kind, ctx)
 
         if not variants:
             log.warning("digest.all_variants_failed", kind=kind)