feat(android): the palette taken from the phone's global search

Not the desktop's slate any more: a blue gradient behind, blocks that are only translucent white laid over it, no borders at all, wide radii, white text. Depth comes from transparency, which is why the frames are gone - a hairline reads as a desktop application immediately.

There is no coloured accent in the reference either: primary and secondary differ by how much white they carry, 30 against 18 per cent. The 2FA code goes white, carried by its size. Nothing is uppercase - the second plane is marked by colour and size alone.

Three compiler traps on the way, all worth knowing: TBrush needs FMX.Graphics in the INTERFACE clause, a fresh TGradient already runs top to bottom, and TForm already owns a parameterless PaintBackground that shadowed the unit's.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

android-client/theme/make-style.ps1

@@ -19,9 +19,9 @@ $src = 'C:\Program Files (x86)\Embarcadero\Studio\23.0\Redist\styles\Fmx\Dark.st
 $dst = Join-Path $PSScriptRoot 'pm-dark.style'
 
 # Doivent suivre les constantes de PMA.Theme.
-$surface = 'xFF1E293B'   # COL_SURFACE
-$border  = 'xFF334155'   # COL_RAISED, en bordure discrete
-$text    = 'xFFE2E8F0'   # COL_TEXT
+$surface = 'x2EFFFFFF'   # COL_RAISED : blanc translucide, sans bordure
+$border  = 'x00000000'   # plus de filet : la reference n'en a aucun
+$text    = 'xFFFFFFFF'   # COL_TEXT
 
 $lines = Get-Content $src
 $patched = 0