feat(mosaico): add Type-C CDC console and automatic download

[eMUQI]

Summary

ESP-Mosaico currently requires BOOT/power operations to enter wired download mode. Enable a Type-C USB OTG CDC console with the upstream USB Serial/JTAG-compatible DTR/RTS reset sequence, allowing a running application to enter ROM download mode from the host.

• Vendor the pinned upstream USB HS Console component, enable it only for Mosaico, and keep application startup available if USB initialization fails.
• Keep CameraBoard GPIO33 ownership independent of the Type-C USB OTG console.
• Document first-install/recovery steps, application-to-ROM port changes, segmented flashing, and console API constraints; include dependency and license records.

Validation

• Built and flashed standalone CDC commit a5eaff0 with ESP-IDF v6.1; no BLE OTA branch changes are included.
• macOS / esptool 5.3.1: entered ROM from application CDC without buttons, wrote the 5,461,504-byte application in six segments to the existing active slot, and verified every segment and the complete image.
• Before reboot, hash checks confirmed bootloader, partition table, NVS, PHY and OTA metadata were unchanged by flashing.
• After booting the standalone image, repeated application CDC → ROM download → watchdog reset → application CDC without buttons.
• Both boots detected SC101IOT and continued camera capture; CDC logs were captured for 30 seconds and 20 seconds without observed crashes or disconnects.
• The original code revision passed all CI checks. The subsequent update only records this hardware validation in the target README.

Long-duration camera/CDC coexistence and Windows behavior remain unverified. USB ports re-enumerate between application and ROM; a single idf.py flash command handling that transition has not been validated. BOOT recovery remains necessary if the application or USB initialization fails. Flash-region checks do not establish runtime pairing acceptance.

[eMUQI]

@codex review

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-03T09:29:17.801139Z	a5eaff0	Manual request

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[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. 🚀

Reviewed commit: a5eaff0bad

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