chore(core/eckhart): invert QR screen colors

[bieleluk]

This PR inverts the colors of Eckhart's QRScreen according to Figma.

TODO

• Figure out the color of the pressed button: asked in Figma thread
• Add [no changelog] to the commit message

[Copilot]

Pull Request Overview

This PR inverts the color scheme for QR code screens in the Eckhart layout to align with new design specifications from Figma. The changes implement a white background with black text/icons instead of the previous dark theme.

• Simplified QR screen component structure by removing action bar and header dependencies
• Added inverted color theme styles for buttons and text
• Updated QR screen layout to use a white background with black text elements

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
core/embed/rust/src/ui/layout_eckhart/theme/mod.rs	Adds new TEXT_SMALL_BLACK style for black text on white background
core/embed/rust/src/ui/layout_eckhart/theme/firmware.rs	Introduces button_header_inverted() style with inverted colors
core/embed/rust/src/ui/layout_eckhart/flow/receive.rs	Updates QR screen instantiation to use simplified constructor
core/embed/rust/src/ui/layout_eckhart/firmware/qr_screen.rs	Complete refactor to use white background, simplified layout without action bar

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[github-actions]

en main(all)

model	device_test	click_test	persistence_test
T2T1	test(all) main(all)	test(all) main(all)	test(all) main(all)
T3B1	test(all) main(all)	test(all) main(all)	test(all) main(all)
T3T1	test(all) main(all)	test(all) main(all)	test(all) main(all)
T3W1	test(all) main(all)	test(all) main(all)	test(all) main(all)

Translations

cs main(all)

model	device_test	click_test
T2T1	test(all) main(all)	test(all) main(all)
T3B1	test(all) main(all)	test(all) main(all)
T3T1	test(all) main(all)	test(all) main(all)
T3W1	test(all) main(all)	test(all) main(all)

de main(all)

model	device_test	click_test
T2T1	test(all) main(all)	test(all) main(all)
T3B1	test(all) main(all)	test(all) main(all)
T3T1	test(all) main(all)	test(all) main(all)
T3W1	test(all) main(all)	test(all) main(all)

es main(all)

model	device_test	click_test
T2T1	test(all) main(all)	test(all) main(all)
T3B1	test(all) main(all)	test(all) main(all)
T3T1	test(all) main(all)	test(all) main(all)
T3W1	test(all) main(all)	test(all) main(all)

fr main(all)

model	device_test	click_test
T2T1	test(all) main(all)	test(all) main(all)
T3B1	test(all) main(all)	test(all) main(all)
T3T1	test(all) main(all)	test(all) main(all)
T3W1	test(all) main(all)	test(all) main(all)

pt main(all)

model	device_test	click_test
T2T1	test(all) main(all)	test(all) main(all)
T3B1	test(all) main(all)	test(all) main(all)
T3T1	test(all) main(all)	test(all) main(all)
T3W1	test(all) main(all)	test(all) main(all)

Latest CI run: 17149896751