docs cleanup and disk usage target change

PLAN.md

@@ -1,40 +1,5 @@
 # Pi Servers -- Roadmap
 
-## Alarm Configuration
-
-Replace the current `randint(30, 60)` test loop in `contents_server.py` with real schedule-driven alarms.
-
-### Config schema
-
-File: `pi/alarm_config.json`
-
-```json
-{
-  "alarm_time": "0700",
-  "alarm_days": ["Mon", "Tue", "Wed", "Thu", "Fri"],
-  "alarm_dates": ["07/20", "10/21"],
-  "alarm_audio": "assets/alarm/alarm_test.wav",
-  "alarm_image": "assets/img/on_alarm.png"
-}
-```
-
-### Field definitions
-
-| Field | Type | Description |
-|-------|------|-------------|
-| `alarm_time` | `string` | 4-digit HHMM (24-hour). Triggers on the 0th second of the minute, or as soon as Python detects it. |
-| `alarm_days` | `string[]` | (Optional) 3-letter day abbreviations: `Mon`, `Tue`, `Wed`, `Thu`, `Fri`, `Sat`, `Sun`. Alarm only fires on listed days. If not supplied, alarms every day. |
-| `alarm_dates` | `string[]` | (Optional) Strings of `MM/DD` format. If both `alarm_days` and `alarm_dates` are set, only `alarm_days` is effective. |
-| `alarm_audio` | `string` | (Optional) Path to WAV file. Relative paths resolve from `pi/`. If not supplied, defaults to `assets/alarm/alarm_test.wav`. |
-| `alarm_image` | `string` | (Optional) Path to status PNG shown during alarm. Relative paths resolve from `pi/`. If not supplied, defaults to `assets/img/on_alarm.png`. |
-
-### Behavior
-
-- On startup, load and validate `alarm_config.json`
-- Each tick (~5s), check if current local time matches `alarm_time` and today's day name is in `alarm_days`, or if today's date is in `alarm_dates`.
-- Fire alarm once per matched minute (debounce so it doesn't re-trigger within the same minute)
-- After alarm completes, return to idle image and resume schedule checking
-
 ## Docker Compose
 
 Containerize the pi servers for easier deployment.
@@ -48,7 +13,7 @@ Single service is simpler. Split services allow independent scaling and restarts
 
 ### Configuration
 
-- Volume mount `assets/` and `alarm_config.json` so they're editable without rebuilding
+- Volume mount `assets/` and `config/alarms.json` so they're editable without rebuilding
 - Expose ports 8765 and 8766
 - Network mode `host` or a bridge with known IPs for ESP32 discovery
 - Restart policy: `unless-stopped`
@@ -61,7 +26,7 @@ The `pi/` directory will become its own git repository.
 
 1. Extract `pi/` into a standalone repo with its own `README.md`, `requirements.txt`, and CI
 2. Add it back to this project as a git submodule
-3. The interface contract between the two repos is the WebSocket protocol -- JSON schemas and binary frame formats documented in `docs/ALARM_PROTOCOL.md`
+3. The interface contract between the two repos is the WebSocket protocol -- JSON schemas and binary frame formats documented in `README.md`
 
 ### Benefits