feat: major platform expansion — Brain service, RSS reader, iOS app, AI assistants, Firefox extension

Brain Service:
- Playwright stealth crawler replacing browserless (og:image, Readability, Reddit JSON API)
- AI classification with tag definitions and folder assignment
- YouTube video download via yt-dlp
- Karakeep migration complete (96 items)
- Taxonomy management (folders with icons/colors, tags)
- Discovery shuffle, sort options, search (Meilisearch + pgvector)
- Item tag/folder editing, card color accents

RSS Reader Service:
- Custom FastAPI reader replacing Miniflux
- Feed management (add/delete/refresh), category support
- Full article extraction via Readability
- Background content fetching for new entries
- Mark all read with confirmation
- Infinite scroll, retention cleanup (30/60 day)
- 17 feeds migrated from Miniflux

iOS App (SwiftUI):
- Native iOS 17+ app with @Observable architecture
- Cookie-based auth, configurable gateway URL
- Dashboard with custom background photo + frosted glass widgets
- Full fitness module (today/templates/goals/food library)
- AI assistant chat (fitness + brain, raw JSON state management)
- 120fps ProMotion support

AI Assistants (Gateway):
- Unified dispatcher with fitness/brain domain detection
- Fitness: natural language food logging, photo analysis, multi-item splitting
- Brain: save/append/update/delete notes, search & answer, undo support
- Madiha user gets fitness-only (brain disabled)

Firefox Extension:
- One-click save to Brain from any page
- Login with platform credentials
- Right-click context menu (save page/link/image)
- Notes field for URL saves
- Signed and published on AMO

Other:
- Reader bookmark button routes to Brain (was Karakeep)
- Fitness food library with "Add" button + add-to-meal popup
- Kindle send file size check (25MB SMTP2GO limit)
- Atelier UI as default (useAtelierShell=true)
- Mobile upload box in nav drawer

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

services/reader/Dockerfile.api

@@ -0,0 +1,22 @@
+FROM python:3.12-slim
+
+WORKDIR /app
+
+RUN apt-get update && apt-get install -y --no-install-recommends libpq-dev && rm -rf /var/lib/apt/lists/*
+RUN pip install --no-cache-dir --upgrade pip
+
+COPY requirements.txt .
+RUN pip install --no-cache-dir -r requirements.txt
+
+RUN adduser --disabled-password --no-create-home appuser
+
+COPY --chown=appuser app/ app/
+
+EXPOSE 8300
+ENV PYTHONUNBUFFERED=1
+
+HEALTHCHECK --interval=30s --timeout=5s --retries=3 \
+  CMD python3 -c "import urllib.request; urllib.request.urlopen('http://127.0.0.1:8300/api/health', timeout=3)" || exit 1
+
+USER appuser
+CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "8300"]