refactor: namespace restructure of entire codebase

Reorganize all source files into a hierarchical namespace structure
with dot-separated unit names matching directory paths.

Major changes:
- src/prog/ -> src/app/ (app.*.pas)
- src/fault/ -> src/arch/x86/fault/ (arch.x86.fault.*.pas)
- src/isr/ -> src/arch/x86/isr/ (arch.x86.isr.*.pas)
- src/include/ -> src/core/ (core.*.pas) + src/arch/x86/
- src/driver/ subtree reorganized with driver.* namespace prefixes
- src/driver/storage/con/ -> src/driver/storage/ctl/ (Windows reserved name fix)
- src/driver/storage/ split into con(ctl)/fs/vol/ subdirectories
- src/driver/net/ flattened from l1-l5 layers to driver.net.*.pas
- kernel.pas -> asuro.pas, faults.pas -> arch.x86.faults.pas
- stdio.pas/syslog.pas -> io/io.stdio.pas, io/io.syslog.pas
- processmanager.pas -> proc/proc.mgr.pas
- lmemorymanager.pas -> memory/memory.heap.pas
- Build scripts moved to toolchain/
- Added compat/ shims for lmemorymanager and types
- Added doc/namespace.md tracking the refactor

197 files changed, 6292 insertions(+), 5526 deletions(-)

src/proc/proc.testprocs.pas

@@ -0,0 +1,60 @@
+{
+    TestProcs - Temporary test processes for validating preemptive scheduling.
+
+    Two processes that each print a message once per second via io.syslog,
+    demonstrating concurrent preemptive execution.
+
+    @author(Kieron Morris <[email protected]>)
+}
+unit proc.testprocs;
+
+interface
+
+uses
+    proc.types, proc.mgr, io.syslog, arch.x86.bda;
+
+procedure init;
+
+implementation
+
+{ Simple busy-wait sleep: spin-yields until approx 'ticks' timer ticks
+  have elapsed (timer runs at ~1024 Hz, so 1024 ticks ~ 1 second). }
+procedure sleep_ticks(ticks : uint16);
+var
+    start, now, elapsed : uint16;
+begin
+    start := BDA^.Ticks;
+    repeat
+        proc_yield;
+        now := BDA^.Ticks;
+        if now >= start then
+            elapsed := now - start
+        else
+            elapsed := (65535 - start) + now + 1;  { handle uint16 wrap }
+    until elapsed >= ticks;
+end;
+
+procedure program1(ctx : PProcessContext);
+begin
+    while ctx^.PendingMsg <> smTerminate do begin
+        io.syslog.logln('PROC1', 'Hello from program 1');
+        sleep_ticks(1024);
+    end;
+end;
+
+procedure program2(ctx : PProcessContext);
+begin
+    while ctx^.PendingMsg <> smTerminate do begin
+        io.syslog.logln('PROC2', 'Hello from program 2');
+        sleep_ticks(1024);
+    end;
+end;
+
+procedure init;
+begin
+    proc.mgr.create('testproc1', @program1, nil, 1);
+    proc.mgr.create('testproc2', @program2, nil, 1);
+    io.syslog.logln('TESTPROCS', 'Two test processes created.');
+end;
+
+end.