Add PDF-based document generation with LibreOffice; fix line numbering and margins

- Add LibreOffice Writer and DejaVu fonts to Dockerfile for PDF generation
- Add PyPDF2 and reportlab to requirements.txt
- Refactor email_sender.py:
  - Enforce 1-inch margins on all sides
  - Isolate line numbering to transcript section only
  - Add generate_pdf_documents() to build:
    - TRANSCRIPT.pdf (cover + transcript)
    - SUMMARY.pdf (cover + summary)
    - COMBINED.pdf (transcript cover + summary + TRANSCRIPT header + transcript)
  - Add page numbers (bottom-right) to all PDFs via reportlab
- Update tasks.py:
  - Use generate_pdf_documents() after creating DOCX files
  - Attach source JSON, MD files, and compiled PDFs in success email
- Add test_docx_generation.py for transcript/summary/combined DOCX testing

tests/test_docx_generation.py

@@ -0,0 +1,96 @@
+"""
+Local test for transcript/summary/combined .docx generation.
+Checks:
+- Line numbering only on transcript pages.
+- Page numbering (X of Y) in footer.
+- Cover pages present and centered.
+- Combined document structure.
+"""
+
+import sys
+import os
+import tempfile
+
+sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+
+from scraibe.email_sender import (
+    create_transcript_docx,
+    create_summary_docx,
+    create_combined_docx,
+)
+
+TRANSCRIPT_TEXT = """[00:00] Speaker 1: Good morning, everyone. Thank you for joining today's meeting.
+[00:12] Speaker 2: Good morning. I'm looking forward to discussing the new requirements.
+[00:25] Speaker 1: Let's start with the timeline. We need to finalize the scope by Friday.
+[00:38] Speaker 2: Agreed. I'll send a summary of the key points after this call.
+[00:45] Speaker 1: Perfect. If there are no other items, we can wrap up here."""
+
+SUMMARY_TEXT = """# Meeting Overview
+## Key Discussion Points
+### Timeline and Scope
+#### Next Steps"""
+
+COVER_DATE = "June 14, 2026"
+TRANSCRIPT_DESC = "Transcript of a project planning meeting discussing timelines and scope."
+SUMMARY_DESC = "Summary of a project planning meeting covering key decisions and next steps."
+
+
+def main():
+    with tempfile.TemporaryDirectory() as tmpdir:
+        print("Using temp directory:", tmpdir)
+
+        # 1) Transcript-only
+        transcript_path = os.path.join(tmpdir, "TRANSCRIPT_TEST.docx")
+        print("Creating transcript-only docx:", transcript_path)
+        create_transcript_docx(
+            text=TRANSCRIPT_TEXT,
+            filename=transcript_path,
+            include_cover=True,
+            cover_date=COVER_DATE,
+            cover_desc=TRANSCRIPT_DESC,
+        )
+        print("OK: transcript-only created.")
+
+        # 2) Summary-only
+        summary_path = os.path.join(tmpdir, "SUMMARY_TEST.docx")
+        print("Creating summary-only docx:", summary_path)
+        create_summary_docx(
+            text=SUMMARY_TEXT,
+            filename=summary_path,
+            include_cover=True,
+            cover_date=COVER_DATE,
+            cover_desc=SUMMARY_DESC,
+        )
+        print("OK: summary-only created.")
+
+        # 3) Combined
+        combined_path = os.path.join(tmpdir, "COMBINED_TEST.docx")
+        print("Creating combined docx:", combined_path)
+        create_combined_docx(
+            transcript_text=TRANSCRIPT_TEXT,
+            summary_text=SUMMARY_TEXT,
+            filename=combined_path,
+            transcript_cover_date=COVER_DATE,
+            transcript_cover_desc=TRANSCRIPT_DESC,
+            summary_cover_date=COVER_DATE,
+            summary_cover_desc=SUMMARY_DESC,
+        )
+        print("OK: combined created.")
+
+        # Basic size sanity checks
+        for path in [transcript_path, summary_path, combined_path]:
+            size = os.path.getsize(path)
+            print(f"File: {os.path.basename(path)} - size: {size} bytes")
+            if size < 10000:
+                print("WARNING: File seems unusually small:", path)
+
+        print("\nAll .docx files generated successfully.")
+        print("Please open them in Word to verify:")
+        print("- Only transcript pages have line numbers.")
+        print("- Footer shows 'X of Y' on all pages.")
+        print("- Cover pages are centered and use the correct date format.")
+        print("- Combined doc order: cover, page break, summary, page break, transcript.")
+
+
+if __name__ == "__main__":
+    main()