docs: README, plan, guides and the site describe what is built now

README: rewritten around what runs (Linux software, Xorg, apk, Linux's drivers), the honest gaps, measured numbers.
plan/: 1.0.md is the finish line, where each clause of the acceptance test stands, and the register (one failing
clause: a root that survives a reboot); built plans (foundations, hybrid, alpine, xorg) and the decided-against one
(wayland) are gone, their content lives in architecture/; roadmap.md is only what is still open.
guides: building/layout/testing/adding-a-driver (Linux code may be used). history: four entries (ls -lR, TLB
shootdowns, MDIO 0x02460246, netlink MSG_TRUNC). Website: cards, stack, download page, docs index.
Code comments that pointed at deleted plan docs point at the architecture docs.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EVRhxi9zpdW2uDUN4FVcao

include/core/dma.h

@@ -26,7 +26,7 @@
 //
 // 4 MB was one framebuffer at 1280x800, which was fine while exactly one driver
 // wanted one. It stopped being fine the day a display driver could be handed to
-// userspace (docs/plan/hybrid.md): either side of that handover **both drivers
+// userspace (docs/architecture/devices.md): either side of that handover **both drivers
 // exist**, and the incoming one has to allocate its framebuffer before the
 // outgoing one lets go of its own. So the real requirement is two framebuffers
 // at once, not one.

include/dev/pci.h

@@ -151,7 +151,7 @@ struct pci_driver {
     void (*attached)(struct pci_dev *, struct device *);
     // Give the device up, so a userspace driver can take it.
     //
-    // docs/plan/hybrid.md is built on the kernel *handing over* a device
+    // docs/architecture/devices.md is built on the kernel *handing over* a device
     // rather than a process wrestling it away: two drivers writing one set of
     // registers is not a subtle failure, it is hardware that appears to have
     // started lying. So the transfer is the incumbent's decision, and this is

include/dev/pciuser.h

@@ -2,7 +2,7 @@
 //
 // /dev/pci -- device access from userspace.
 //
-// docs/plan/hybrid.md, mechanisms 2 and 4: MMIO and DMA to a process. This is
+// docs/architecture/devices.md, mechanisms 2 and 4: MMIO and DMA to a process. This is
 // the interface a driver that does not live in the kernel talks to, and it is
 // deliberately about *PCI devices*, not about any particular driver model.
 //
@@ -23,7 +23,7 @@
 //
 // There is no IOMMU. A process holding a DMA buffer can point the device at
 // any physical address, so this isolates a driver against its own *bugs* and
-// not against its own *intent*. docs/plan/hybrid.md says so at length and it
+// not against its own *intent*. docs/architecture/devices.md says so at length and it
 // remains true here: a crashed driver that restarts instead of taking the
 // machine down is the whole benefit, and it is not a security boundary.
 

include/dev/virtio.h

@@ -4,7 +4,7 @@
 //
 // It lived next to the driver while exactly one driver read it, with a note
 // saying it should move when a second reader appeared. One has: cmd/vgpud is
-// the same device driven from userspace (docs/plan/hybrid.md's first
+// the same device driven from userspace (docs/architecture/devices.md's first
 // eviction), and it needs the same register offsets and the same commands.
 //
 // Still one file rather than transport-and-protocol split in two. Both readers

include/net/socket.h

@@ -63,7 +63,7 @@
 // is not a number: it names an object the kernel already knows, and handing it
 // over is the difference between "here is a buffer" and "here is a *copy* of a
 // buffer". Wayland's wl_shm_create_pool passes one and has no integer-shaped
-// alternative; docs/plan/hybrid.md's mechanism 1 is this and nothing else.
+// alternative; docs/architecture/devices.md's mechanism 1 is this and nothing else.
 //
 // Every structure below is Linux's, byte for byte, because a musl-linked
 // program builds them with Linux's headers and we do not get a vote. The