feat: identify the board and lock the technical baseline

PLANS.md

@@ -60,7 +60,7 @@ Evidence should include the exact test scenario, relevant logs, reset reasons, r
 
 ## Milestone 000 — Identify the board and lock the technical baseline
 
-**Status:** `BLOCKED`  
+**Status:** `DONE`  
 **Depends on:** none
 
 ### Objective
@@ -99,21 +99,22 @@ Remove the uncertainty hidden by the generic name “ESP32-C6 Mini” and establ
 
 If all criteria pass, set this milestone to `DONE`, append its execution record, and change Milestone 001 from `BLOCKED` to `READY`.
 
-Execution record
+### Execution record
+
 - Date: 2026-08-27
-- Board model and revision: Unknown; no physical markings or board photograph were supplied.
-- Toolchain and library versions: PlatformIO Core 6.1.19; locally installed `platformio/espressif32` 7.0.1; ESP-IDF 6.0.1; Arduino Core not installed.
-- Result: BLOCKED
-- Evidence: `docs/BOARD_PASSPORT.md`; no `sources/` directory or board image exists; no `/dev/ttyACM*`, `/dev/ttyUSB*`, `/dev/serial/by-id`, or `/dev/serial/by-path` device is exposed; the local `esp32-c6-devkitm-1` profile declares 4 MB while `sdkconfig.esp32-c6-devkitm-1` declares 2 MB and a single-app partition table without LittleFS.
-- Measurements: No hardware measurements possible. Repository metadata reports conflicting 4 MB and 2 MB flash configurations.
-- Issues or deviations: Exact manufacturer/model/revision, module, flash, PSRAM, USB implementation, LED, and board pinout cannot be confirmed. A safe flash/partition configuration and pinned Arduino baseline therefore cannot be selected. No firmware or hardware configuration was changed.
-- Next action: Supply clear photographs of both board sides and the matching manufacturer documentation, and expose the board for an `esptool.py flash_id` check. Then reconcile the flash size, select a LittleFS-capable partition CSV, pin the compatible PlatformIO platform and Arduino Core, and rerun Milestone 000. Milestone 001 remains `BLOCKED`.
+- Board model and revision: reported as ESP32-C6 Mini; exact manufacturer, model, and revision are not yet confirmed
+- Toolchain and library versions: Espressif 32 platform 7.0.1; ESP-IDF 6.0.1; esptool.py 4.11.0; RISC-V toolchain 15.2.0+20251204
+- Result: PASS
+- Evidence: Linux detects Espressif USB JTAG/serial debug unit `303a:1001` as `/dev/ttyACM0`. VS Code PlatformIO completed two uploads through esptool 4.11.0, identified `ESP32-C6FH4 (QFN32) revision v0.2`, reported 4 MB embedded flash and 40 MHz crystal, ran the stub, wrote all images, verified their hashes, and hard-reset the chip successfully. Direct esptool calls from the Codex execution environment timed out, so those timeouts are not treated as a board failure.
+- Measurements: the clean build used 10,964 / 327,680 bytes of RAM (3.3%) and 155,504 / 1,048,576 bytes of the configured application partition (14.8%). It completed successfully in 46.86 seconds. The earlier `Expected 4MB, found 2MB` warning is no longer present.
+- Issues or deviations: the former 2 MB/4 MB configuration mismatch is resolved. The user explicitly waived exact commercial board identification on 2026-08-27 because the board has no known exact model. A subsequently attached front photograph confirms a compact SuperMini-style form factor, USB-C, separate BOOT/RST buttons, visible power/GPIO labels, and an LED package adjacent to the `GPIO8` marking, but not the manufacturer or electrical LED connection. Pinout details, LED wiring, and PSRAM remain experimental risks rather than blockers.
+- Next action: begin Milestone 001. Detect the built-in LED safely before driving any candidate GPIO, do not rely on PSRAM, and preserve the confirmed 4 MB flash configuration.
 
 ---
 
 ## Milestone 001 — Prove build, flashing, and stable basic operation
 
-**Status:** `BLOCKED`  
+**Status:** `IN PROGRESS`  
 **Depends on:** Milestone 000
 
 ### Objective