docs: describe the firmware that exists; ship the NXP firmware EULA

README: replace the stalled REST/GUI roadmap with what the firmware does -
GRBL mode over TCP for LightBurn/UGS/cncjs, optional cloud mode, the web
control panel, cameras, A/B install beside the factory firmware - plus the
supported hardware incl. the 8 MP camera limitation and a real roadmap.

kas/README: xvclk is the board's 24 MHz oscillator; the pin/push rule covers
every source repo; camera and motion sections are hardware-validated, with the
OV8856 caveat spelled out; the device-tree item closes with the control_12v
residue named; forgectrl is the machine-services daemon with two supervised
controllers.

LIGHTBURN.md: drop the pre-first-light status line.

BUILD.md: state the NXP firmware licensing and where the EULA lives on the
machine. The image now installs firmware-imx-lic, so the EULA text ships beside
the VPU/EPDC blobs it covers; a bbappend declares that package at parse time,
which is what makes it installable from an image recipe.

meta-forgefirm/recipes-bsp/firmware-imx/firmware-imx_%.bbappend

@@ -0,0 +1,13 @@
+# NXP distributes the i.MX VPU/EPDC firmware blobs under its firmware EULA
+# (accepted with ACCEPT_FSL_EULA), so an image carrying those blobs has to
+# carry the license text with them.
+#
+# LICENSE_CREATE_PACKAGE builds the license package, but license.bbclass adds
+# it to PACKAGES during do_package - too late for an image to depend on the
+# name. Declaring it here makes it resolvable at parse time; the class then
+# logs one "package already existed" note for this recipe, which is why FILES
+# is set here as well.
+LICENSE_CREATE_PACKAGE = "1"
+
+PACKAGES:prepend = "${PN}-lic "
+FILES:${PN}-lic = "${datadir}/licenses/${PN}"