Enhance newsletter functionality and UI improvements

- Introduce `create_outlook_html` function for generating Outlook-compatible newsletter HTML.
- Update dashboard to include `outlook_html` in the response.
- Modify newsletter generation logic to support separate handling of Outlook HTML.
- Improve CSS styles for newsletter preview and layout adjustments.
- Add new button for downloading HTML directly from the dashboard.

app/main.py

@@ -22,6 +22,7 @@ from app.services.newsletter import (
     DEFAULT_DISPLAY,
     article_url,
     create_html,
+    create_outlook_html,
     create_plain_text,
     create_subject,
     filter_articles,
@@ -189,6 +190,7 @@ async def dashboard(request: Request, db: Session = Depends(get_db), current_use
         "articles_new": [],
         "articles_edited": [],
         "raw_html": "",
+        "outlook_html": "",
         "plain_text": "",
         "filters": {
             "days": 30,
@@ -226,6 +228,7 @@ async def dashboard_generate(
     articles_edited: list = []
     plain_text = ""
     raw_html = ""
+    outlook_html = ""
     try:
         articles = await wiki_service.get_recent_changes(days=days, only_edited=only_edited_flag)
         filtered = filter_articles(articles, category_filter=category or None)
@@ -233,6 +236,7 @@ async def dashboard_generate(
         title = create_subject(days, category)
         plain_text = create_plain_text(filtered, days, display, category)
         raw_html = create_html(filtered, days, display, category)
+        outlook_html = create_outlook_html(filtered, days, display, category)
         run_scheduled_send_if_due(db, title, raw_html, plain_text)
     except WikiFetchError as exc:
         wiki_error = exc.message
@@ -243,6 +247,7 @@ async def dashboard_generate(
             "articles_new": articles_new,
             "articles_edited": articles_edited,
             "raw_html": raw_html,
+            "outlook_html": outlook_html,
             "plain_text": plain_text,
             "filters": {
                 "days": days,