Refactor everything

We now hijack existing system functions to integrate with `WinMgr`,
instead of `Spawn`ing our own `SaphirTask`.

Also, you can now use `Saphir(Bool)` to toggle enable/disable the
features.

There is a global var `saphir` which values are set by `Defaults.HC` for
colors and other behaviors; these values can be changed at any time.

Saphir/WinMgr.HC

@@ -0,0 +1,91 @@
+#define SAPHIR_CURSOR_PATCH_ADDR &DocRecalc + 0x2c62
+
+U0 saphir_update_cursor()
+{
+    U16 res = 0xb4;
+    res |= ((saphir.cursor.fg & 0xf) << 4 | (saphir.cursor.bg & 0xf)) << 8;
+    MemCpy(SAPHIR_CURSOR_PATCH_ADDR, &res, 2);
+    MemSet(SAPHIR_CURSOR_PATCH_ADDR + 0x02, 0x90, 3);
+}
+
+CDoc* saphir_DocBorder(U64)
+{
+    U64 addr = Caller;
+    if (addr >= &DocEd && addr <= (&DocEd + sizeof(DocEd))) {
+        asm {
+            MOV RAX, &DocBorder
+            ADD RAX, 6
+            JMP RAX
+        }
+    }
+
+    CTask* task = sys_task_being_scrn_updated;
+    if (saphir.doc_cursor_state) {
+        task->display_doc->flags = saphir.doc_cursor_state;
+        saphir.doc_cursor_state = 0;
+    }
+    task->win_bottom = MinI64(task->win_bottom, TEXT_ROWS - 3);
+    if (task != sys_focus_task) {
+        return NULL;
+    }
+    if (ac.task) {
+        Kill(ac.task);
+        ac.task = NULL;
+    }
+    saphir_update_cursor;
+    gr.dc->color = BLACK;
+    GrRect(gr.dc, 0, GR_HEIGHT - 8, GR_WIDTH, 8);
+    gr.dc->color = LTGRAY;
+    GrPrint(gr.dc, 0, GR_HEIGHT - 8, "[0x%08x] %s", task,
+        task->task_title);
+
+    return NULL;
+}
+
+U8 saphir_DrvTextAttrGet(U64)
+{
+    U64 addr = Caller;
+    if (addr >= &DrvRep && addr <= (&DrvRep + sizeof(DrvRep))) {
+        asm {
+            MOV RAX, &DrvTextAttrGet
+            ADD RAX, 6
+            POP R11
+            JMP RAX
+        }
+    }
+    if (addr >= &TaskInit && addr <= (&TaskInit + sizeof(TaskInit))) {
+        return NULL;
+    }
+
+    if (sys_focus_task == sys_task_being_scrn_updated) {
+        return (saphir.border.focus_bg & 0xf) << 4 | (saphir.border.focus_fg & 0xf);
+    }
+    if (!saphir.doc_cursor_state) {
+        saphir.doc_cursor_state = sys_task_being_scrn_updated->display_doc->flags;
+        DocCursor(, sys_task_being_scrn_updated->display_doc);
+    }
+    return (saphir.border.bg & 0xf) << 4 | (saphir.border.fg & 0xf);
+}
+
+U0 saphir_cursor(Bool enable)
+{
+    switch (enable) {
+    case 0:
+        MemCpy(SAPHIR_CURSOR_PATCH_ADDR, &saphir.cursor.stub, 8);
+        return;
+    default:
+        MemCpy(&saphir.cursor.stub, SAPHIR_CURSOR_PATCH_ADDR, 8);
+        saphir_update_cursor;
+        return;
+    }
+}
+
+Bool saphir_Blink(F64 Hz = 2.5)
+{
+    if (!saphir.blink) {
+        return 1;
+    }
+    if (!Hz)
+        return 0;
+    return ToI64(cnts.jiffies * 2 * Hz / JIFFY_FREQ) & 1;
+}