Firmware version: <version.txt>-<git short hash>, starting at 0.0.1

e.g. 0.0.1-1d613b1: the first part is set by hand, the hash says which
commit was built. No dirty flag (the build always patches cspot).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/aes67-core-base.md

@@ -125,7 +125,7 @@ When this device is the GM, offset/frequency/delay show "–".
 
 ## Firmware update (OTA)
 - Partition table: nvs, otadata, phy_init, ota_0, ota_1 (no factory app). Size the slots from flash_id; e.g. on 16 MB, 2 × 6 MB leaves room for growth (cspot + TLS + codecs). Keep NVS outside the app slots so config survives updates.
-- Version: `PROJECT_VER` from the first line of `version.txt` (set by hand, e.g. `1.2.0`), read at runtime from `esp_app_get_description()`; also reported as `status.fw`.
+- Version: `PROJECT_VER` = `<version.txt>-<git short hash>` (e.g. `0.0.1-1d613b1`; the first part set by hand), read at runtime from `esp_app_get_description()`; also reported as `status.fw`.
 - API:
   - GET /api/ota -> {version, project, build_date, idf, running, previous, previous_version, pending_verify, can_rollback}
   - POST /api/ota: raw .bin as `application/octet-stream`, streamed with esp_ota_begin/write/end into the inactive slot (never buffered whole in RAM). 200 then reboot; 4xx with a message if rejected.

docs/user-guide.md

@@ -176,8 +176,8 @@ The log shows PTP lock/unlock, source switches, stream errors and firmware updat
 - asks for a hostname, stream name and multicast address.
 
 **Making an update file:**
-1. Set the version in **`version.txt`** (first line, e.g. `1.0.0`). This is what the page shows under *Firmware* and *Status*.
-2. Build: `idf.py build`.
+1. Set the version in **`version.txt`** (first line, e.g. `0.0.2`) and commit your changes.
+2. Build: `idf.py build`. The firmware version becomes `<version>-<commit>`, e.g. `0.0.2-1d613b1`, as shown under *Firmware* and *Status*.
 3. The update file is **`build/aes67_p4.bin`**. Upload it in the *Firmware* section, or with the `curl` command above.
 
 The .bin is for ESP32-P4 chips of **revision v1.x** (the current Waveshare boards). A board with a v3 chip needs a build for that revision; the flash script refuses it with a hint.