feat: Implement email sending utilities and templates for job notifications

- Added email_service.py for sending emails with SMTP configuration.
- Introduced email_templates.py to render job alert email subjects and bodies.
- Enhanced scraper.py to extract contact information from job listings.
- Updated settings.js to handle negative keyword input validation.
- Created email.html and email_templates.html for managing email subscriptions and templates in the admin interface.
- Modified base.html to include links for email alerts and templates.
- Expanded user settings.html to allow management of negative keywords.
- Updated utils.py to include functions for retrieving negative keywords and email settings.
- Enhanced job filtering logic to exclude jobs containing negative keywords.

web/email_templates.py

@@ -0,0 +1,106 @@
+"""Email templates for job notifications."""
+
+from __future__ import annotations
+
+from datetime import datetime, UTC
+from typing import Iterable, Mapping, Dict, Any
+
+DEFAULT_DATETIME_FORMAT = "%Y-%m-%d %H:%M"
+DEFAULT_JOB_ALERT_SUBJECT = "{count_label}{scope}"
+DEFAULT_JOB_ALERT_BODY = (
+    "Hi,\n\n{intro_line}{jobs_section}\n\nGenerated at {timestamp} UTC.\n"
+    "You are receiving this message because job alerts are enabled.\n"
+)
+
+
+class _SafeDict(dict):
+    def __missing__(self, key: str) -> str:
+        return ""
+
+
+def _format_template(template: str, context: Dict[str, Any]) -> str:
+    safe_context = _SafeDict(
+        {k: ("\n".join(str(v) for v in context[k]) if isinstance(
+            context[k], list) else context[k]) for k in context}
+    )
+    return template.format_map(safe_context)
+
+
+def render_job_alert_email(
+    jobs: Iterable[Mapping[str, object]],
+    *,
+    region: str | None = None,
+    keyword: str | None = None,
+    generated_at: datetime | None = None,
+    template_override: Mapping[str, str] | None = None,
+) -> dict[str, Any]:
+    """Render the subject/body for a job alert email.
+
+    Returns a dict with subject/body strings and the context used to render them.
+    """
+
+    job_list = list(jobs)
+    generated_at = generated_at or datetime.now(UTC)
+    timestamp = generated_at.strftime(DEFAULT_DATETIME_FORMAT)
+
+    scope_parts = []
+    if region:
+        scope_parts.append(f"region: {region}")
+    if keyword:
+        scope_parts.append(f"keyword: {keyword}")
+    scope = " (" + ", ".join(scope_parts) + ")" if scope_parts else ""
+
+    job_lines: list[str] = []
+    for index, job in enumerate(job_list, start=1):
+        title = str(job.get("title", "Untitled"))
+        company = str(job.get("company", "Unknown company"))
+        location = str(job.get("location", "N/A"))
+        url = str(job.get("url", ""))
+        line = f"{index}. {title} — {company} ({location})"
+        job_lines.append(line)
+        if url:
+            job_lines.append(f"   {url}")
+
+    if job_lines:
+        jobs_section = "\n" + "\n".join(job_lines)
+    else:
+        jobs_section = "\nNo jobs matched this alert."
+    jobs_message = jobs_section.strip()
+    context: Dict[str, Any] = {
+        "count": len(job_list),
+        "count_label": "No new jobs" if not job_list else f"{len(job_list)} new jobs",
+        "scope": scope,
+        "region": region or "",
+        "keyword": keyword or "",
+        "timestamp": timestamp,
+        "generated_at": generated_at,
+        "intro_line": "Here are the latest jobs discovered by the scraper:",
+        "jobs_message": jobs_message,
+        "jobs_section": jobs_section,
+        "jobs_lines": job_lines,
+        "has_jobs": bool(job_list),
+    }
+
+    template = template_override
+    if template is None:
+        try:
+            from web.db import get_email_template_by_slug
+
+            template = get_email_template_by_slug("job-alert")
+        except Exception:
+            template = None
+
+    template_subject = (template or {}).get(
+        "subject") or DEFAULT_JOB_ALERT_SUBJECT
+    template_body = (template or {}).get("body") or DEFAULT_JOB_ALERT_BODY
+
+    subject = _format_template(template_subject, context)
+    body = _format_template(template_body, context)
+
+    result = {
+        "subject": subject,
+        "body": body,
+        "context": context,
+        "template_slug": (template or {}).get("slug", "job-alert"),
+    }
+    return result