Auto-commit: v2.10 — Fix Huey consumer never starting (loglevel= TypeError)

Root cause: Consumer(huey, workers=1, worker_type='thread', loglevel=20)
raised TypeError on every app start because Huey 2.6.0 does not accept
a `loglevel` keyword argument. The exception was silently caught and only
printed to stdout, so the consumer never ran and all tasks stayed 'queued'
forever — causing the 'Preparing environment / Waiting for logs' hang.

Fixes:
- web/app.py: Remove invalid `loglevel=20` from Consumer(); configure
  Huey logging via logging.basicConfig(WARNING) instead. Add persistent
  error logging to data/consumer_error.log for future diagnosis.
- core/config.py: Replace emoji print() calls with ASCII-safe equivalents
  to prevent UnicodeEncodeError on Windows cp1252 terminals at import time.
- core/config.py: Update VERSION to 2.9 (was stale at 1.5.0).
- ai_blueprint.md: Bump to v2.10, document root cause and fixes.

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

ai_blueprint.md

@@ -1,4 +1,4 @@
-# AI Context Optimization Blueprint (v2.9)
+# AI Context Optimization Blueprint (v2.10)
 
 This blueprint outlines architectural improvements for how AI context is managed during the writing process. The goal is to provide the AI (Claude/Gemini) with **better, highly-targeted context upfront**, which will dramatically improve first-draft quality and reduce the reliance on expensive, time-consuming quality checks and rewrites (currently up to 5 attempts).
 
@@ -171,3 +171,4 @@ The UI gets stuck indefinitely because the background Huey worker thread hangs b
 11. ✅ **(v2.7)** Series Continuity Fix: `series_metadata` (is_series, series_title, book_number, total_books) injected as `SERIES_CONTEXT` into `story/planner.py` (`enrich`, `plan_structure`), `story/writer.py` (`write_chapter`), and `story/editor.py` (`evaluate_chapter_quality`) prompts with position-aware guidance per book number. *(Implemented v2.7)*
 12. ✅ **(v2.8)** Infrastructure & UI Bug Fixes: API timeouts (180s generation, 30s list_models) in `ai/models.py` + `ai/setup.py`; Huey consumer moved to module level with reloader guard in `web/app.py`; Jinja2 `UndefinedError` fix for `tropes`/`formatting_rules` in `project_setup.html`; `project_setup_wizard` now renders form instead of silent redirect when models fail; `create_project_final` `enrich()` call fixed to use correct per-book blueprint structure. *(Implemented v2.8)*
 13. ✅ **(v2.9)** Background Task Hang Fixes: OAuth headless guard in `ai/setup.py` (skips `run_local_server` in non-main threads, logs warning, falls back to ADC); SQLite `timeout=30, check_same_thread=False` on all connections in `web/tasks.py`; initial log file touched immediately in `generate_book_task` so UI polling never sees an empty/missing file. *(Implemented v2.9)*
+14. ✅ **(v2.10)** Huey Consumer Startup Fix: `Consumer.__init__()` in Huey 2.6.0 does NOT accept a `loglevel` keyword argument — the previous call `Consumer(huey, workers=1, worker_type='thread', loglevel=20)` raised `TypeError` on every app start, silently killing the consumer. All tasks stayed `queued` forever, causing the "Preparing environment / Waiting for logs" hang. Fixed by removing `loglevel=20`; Huey logging now configured via `logging.basicConfig`. Consumer startup errors now written to `data/consumer_error.log` for diagnosis. Also removed emoji characters from `print()` calls in `core/config.py` that caused `UnicodeEncodeError` on Windows `cp1252` terminals. Updated `VERSION` to `2.9` in `config.py`. *(Implemented v2.10)*