v1.4.0: Organic writing, speed, and log improvements

Organic book quality:
- write_chapter: strip key_events spoilers from character context so the writer
  doesn't know planned future events when writing early chapters
- write_chapter: added next_chapter_hint — seeds anticipation for the next scene
  in the final paragraphs of each chapter for natural story flow
- write_chapter: added DIALOGUE VOICE instruction referencing CHARACTER TRACKING
  speech styles so every character sounds distinctly different
- Lowered SCORE_AUTO_ACCEPT 9→8 to stop over-refining already-professional drafts

Speed improvements:
- check_pacing: reduced from every chapter to every other chapter (~50% fewer calls)
- refine_persona: reduced from every 3 to every 5 chapters (~40% fewer calls)
- Resume summary rebuild: uses first + last-4 chapters instead of all chapters
  to avoid massive prompts when resuming mid-book
- Summary context sent to writer capped at 8000 chars (most-recent events)
- update_tracking text cap lowered 500000→20000 (covers any realistic chapter)

Logging and progress bars:
- Progress bar updates at chapter START, not just after completion
- Chapter banner logged before each write so the log shows which chapter is active
- Word count logged after first draft (e.g. "Draft: 2,341 words (target: ~2200)")
- Word count added to chapter completion TIMING line
- Pacing check now logs "Pacing OK" with reason when no intervention needed
- utils: added log_banner() helper for phase separator lines

UI:
- run_details.html: log lines are now phase-coloured (WRITER=cyan, ARCHITECT=green,
  TIMING=gray, SYSTEM=yellow, TRACKER=purple, RESUME=orange, etc.)
- Status bar shows current active phase (e.g. "Status: Running — WRITER")

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

modules/utils.py

@@ -71,7 +71,11 @@ def get_sorted_book_folders(run_dir):
     return sorted(subdirs, key=sort_key)
 
 # --- SHARED UTILS ---
-def log(phase, msg): 
+def log_banner(phase, title):
+    """Log a visually distinct phase separator line."""
+    log(phase, f"{'─' * 18} {title} {'─' * 18}")
+
+def log(phase, msg):
     timestamp = datetime.datetime.now().strftime('%H:%M:%S')
     line = f"[{timestamp}] {phase:<15} | {msg}"
     print(line)