[OhadMeir]

Tracked on [RSDSO-21514]

D400 now behaves like D500: the SDK no longer downloads, embeds, or auto-suggests a "recommended" firmware binary. Users update firmware exclusively with a user-supplied .bin via rs-fw-update -f or the viewer's "Update Firmware..." menu, with binaries downloaded from https://dev.realsenseai.com/docs/firmware-updates.

Changes
CMake: deleted IMPORT_DEPTH_CAM_FW option, the entire common/fw/ subproject (which downloaded and embedded D4XX_FW_Image-*.bin), the -DINTERNAL_FW define, and the android-config override.
Core SDK: stopped registering RS2_CAMERA_INFO_RECOMMENDED_FIRMWARE_VERSION for D400 (src/ds/d400/d400-device.{h,cpp}); dropped the dead "uncomment when D500 FW exists" line from d500-device.{h,cpp}. Public enum kept for ABI.
Viewer / common UI: removed check_for_bundled_fw_update and should_bundle_fw_be_recommended, the bundled-FW notification, the "Recommend Bundled Firmware" settings checkbox, and the dead recommend_updates / allow_rc_firmware config keys. Added a discreet "Download firmware..." hyperlink in the device-info panel.
rs-fw-update tool: unchanged (already file-only).
Android wrapper: removed the gradle downloadFirmware task and the R.raw.fw_d4xx auto-update branch in FirmwareUpdateProgressDialog; the dialog now requires a user-supplied file path.
REST API + react-viewer: deleted the POST /firmware/{id}/update endpoint plus all bundle-resolution helpers; replaced the "Install update" button with a "Download firmware →" link. (Neither surface had a file-upload path before — net effect: FW update is no longer possible via REST/React, matching the rest of the cleanup.)
Tests: test-fw-update.py now requires --custom-fw-d400 / --custom-fw-d555 and skips with a warning otherwise.
Docs: removed the "Offline updates" section from doc/viewer-sw-fw-update.md; added a "Where to get firmware" pointer; removed the IMPORT_DEPTH_CAM_FW row from build.md; updated testing.md to note the now-mandatory custom-FW flag.

Companion PR
A separate PR in librealsense-deploy sets CUSTOM_FW_D400_URL to a real signed-FW URL (Signed_Image_UVC_5_17_0_10.bin) by default in three Groovy files, so Jenkins test-fw-update continues to exercise D400 instead of silently skipping after this change lands.

[Copilot]

Pull request overview

This PR removes the bundled D400 firmware pipeline and shifts firmware updates toward user-supplied/downloaded firmware files across core SDK, viewer/common UI, REST/react viewer, Android, tests, docs, and build configuration.

Changes:

• Removed bundled firmware CMake target/options, generated firmware resources, and D400 recommended-firmware registration.
• Removed REST/react-viewer bundled firmware update flow and replaced UI install prompts with firmware download links.
• Updated Android, unit-test, and documentation paths to require externally supplied firmware binaries.

Reviewed changes

Copilot reviewed 37 out of 37 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
CMakeLists.txt	Stops adding bundled firmware subproject.
CMake/lrs_options.cmake	Removes IMPORT_DEPTH_CAM_FW option.
CMake/android_config.cmake	Removes Android override for bundled firmware import.
common/fw/CMakeLists.txt	Deletes bundled firmware download/embed target.
common/fw/empty.c	Deletes empty firmware target source.
common/fw/firmware-version.h	Deletes bundled D400 firmware version definition.
common/fw/fw.c.in	Deletes firmware binary C source template.
common/fw/fw.h.in	Deletes firmware access header template.
common/fw/fw.rc	Deletes Windows firmware resource include.
common/fw/fw.rc.in	Deletes Windows firmware resource template.
common/fw-update-helper.h	Removes bundled firmware helper APIs; adds download URL helper.
common/fw-update-helper.cpp	Removes bundled image resolution and exposes firmware download URL.
common/device-model.h	Removes bundled firmware notification/config declarations.
common/device-model.cpp	Removes bundled firmware notification logic and adds firmware download link in device info.
common/viewer.cpp	Removes “Recommend Bundled Firmware” setting.
common/ux-window.cpp	Removes default config keys for bundled/RC firmware recommendations.
src/ds/d400/d400-device.h	Removes D400 recommended firmware member.
src/ds/d400/d400-device.cpp	Stops using bundled firmware version and registering recommended firmware info.
src/ds/d500/d500-device.h	Removes unused D500 recommended firmware member.
src/ds/d500/d500-device.cpp	Removes dead commented recommended firmware registration.
tools/tools_common.cmake	Removes firmware target linkage and INTERNAL_FW define.
tools/realsense-viewer/realsense-viewer.cpp	Removes bundled firmware header include/define fallback.
tools/enumerate-devices/readme.md	Updates sample output to omit recommended firmware version.
wrappers/android/tools/camera/build.gradle	Removes Gradle firmware download task.
wrappers/android/tools/camera/src/main/java/com/intel/realsense/camera/FirmwareUpdateProgressDialog.java	Requires user-supplied firmware file instead of raw bundled resource.
wrappers/rest-api/app/api/endpoints/firmware.py	Removes REST firmware update endpoint.
wrappers/rest-api/app/services/rs_manager.py	Removes bundled firmware discovery/download/update flow and reports unknown/no recommended firmware.
wrappers/rest-api/tools/react-viewer/src/api/client.ts	Removes firmware update API and socket progress callbacks.
wrappers/rest-api/tools/react-viewer/src/components/DevicePanel.tsx	Removes install/update modal flow and adds firmware download link.
wrappers/rest-api/tools/react-viewer/src/components/FirmwareProgressModal.tsx	Deletes firmware progress modal component.
wrappers/rest-api/tools/react-viewer/src/store/index.ts	Removes firmware update store action/state transitions.
wrappers/rest-api/tools/react-viewer/tests/mocks/api-handlers.ts	Updates firmware mock response and removes update mock endpoint.
wrappers/rest-api/tools/react-viewer/tests/unit/components/DevicePanel.test.tsx	Removes mocked updateFirmware action.
unit-tests/test-fw-update.py	Requires custom firmware path and removes bundled image lookup.
doc/viewer-sw-fw-update.md	Replaces offline bundled firmware docs with download instructions.
.github/skills/testing.md	Documents mandatory custom firmware path for firmware-update tests.
.github/skills/build.md	Removes IMPORT_DEPTH_CAM_FW from build flag docs.

[Nir-Az]

Please make sure rest API viewer works with this change

[Nir-Az]

Checked