docs: clear briefing remnants and document journal system

The Briefing system was retired weeks ago and replaced with the
conversational Journal, but several current-state docs still
described it as live. Updates:

architecture.md
- settings keys: briefing_enabled / briefing_locations / office_days →
  journal_config (JSON: locations, temp_unit, prep schedule)
- conversation_type: chat/briefing/mcp → chat/journal/mcp
- briefing_date column → day_date on Conversation
- "Briefing-Related Tables" section: dropped rss_feeds + rss_items
  rows (retired with PR #43); kept weather_cache and clarified that
  lat/lon now live in journal_config.locations, not on the cache row
- routes/chat.py description: dropped trailing "briefing conversation
  routes" mention
- routes/briefing.py → routes/journal.py with the current endpoint
  shape (config / today / day / days / weather / moments / trigger-
  prep)
- services/briefing_pipeline + scheduler + conversations + profile →
  services/journal_prep + journal_pipeline + journal_scheduler +
  journal_search/moments + user_profile.build_profile_context

features.md
- "Daily Briefing" section rewritten as "Daily Journal":
  conversational, single morning prep, right rail with weather +
  upcoming events, profile-tab configuration, "what the assistant
  has learned" framing
- Settings table: dropped Briefing tab row, added Profile tab row,
  fixed Notifications row's stale briefing-push reference

api-reference.md
- /api/briefing/* endpoints replaced with /api/journal/* — config,
  today/day/days, trigger-prep, weather (cached/current/refresh/
  geocode), moments

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

docs/api-reference.md

@@ -145,23 +145,22 @@ All endpoints require login (session cookie or `Authorization: Bearer <api-key>`
 |--------|------|-------------|
 | GET | `/api/search` | Semantic + keyword search across notes and tasks. Params: `q`, `type` (`note`/`task`/`all`), `limit` |
 
-## Briefing
+## Journal
 
 | Method | Path | Description |
 |--------|------|-------------|
-| GET | `/api/briefing/config` | Get briefing configuration |
-| PUT | `/api/briefing/config` | Save briefing configuration |
-| GET | `/api/briefing/feeds` | List RSS feeds |
-| POST | `/api/briefing/feeds` | Add RSS feed `{url, name?, category?}` |
-| DELETE | `/api/briefing/feeds/:id` | Delete feed |
-| POST | `/api/briefing/feeds/refresh` | Trigger immediate feed refresh → `{feeds_refreshed, new_items}` |
-| GET | `/api/briefing/weather` | Get weather configuration |
-| PUT | `/api/briefing/weather` | Save weather locations |
-| POST | `/api/briefing/weather/geocode` | Geocode address `{query}` → `{lat, lon, label}` |
-| POST | `/api/briefing/trigger` | Manually fire a briefing slot `{slot}` |
-| GET | `/api/briefing/conversations` | List past briefing conversations |
-| GET | `/api/briefing/conversations/today` | Get/create today's briefing conversation |
-| GET | `/api/briefing/conversations/:id/messages` | Get messages for a briefing conversation |
+| GET | `/api/journal/config` | Get journal configuration (locations, temp_unit, prep schedule) |
+| PUT | `/api/journal/config` | Save journal configuration; live-reschedules the prep job |
+| GET | `/api/journal/today` | Get/create today's journal conversation + messages |
+| GET | `/api/journal/day/:iso` | Get a specific day's journal conversation (read-only) |
+| GET | `/api/journal/days` | List dates with journal content, newest first |
+| POST | `/api/journal/trigger-prep` | Force-regenerate today's prep (or `{date}` for a specific day) |
+| GET | `/api/journal/weather` | Cached weather rows; auto-refreshes stale rows in the background |
+| GET | `/api/journal/weather/current` | Live current conditions for the primary configured location |
+| POST | `/api/journal/weather/refresh` | Manual refresh of all configured locations |
+| POST | `/api/journal/weather/geocode` | Geocode place name `{query}` → `{lat, lon, label}` |
+| POST | `/api/journal/moments/:id/update` | Update a recorded moment |
+| DELETE | `/api/journal/moments/:id` | Delete a moment |
 
 ## Settings