deps: 跟随 openkal 的开发线 (#1)

* deps: 改用 git + 分支跟随 openkal 的开发线

同时把 origin 换成 SSH:它此前指向 HTTPS,而这个账号在那条路径上没有写权限 ——
报出来的是 403,读起来像仓库不存在。

* deps: 例子也要跟着这条线

例子仍用版本号依赖 openkal,而仓库本身改成了 git 依赖 —— 两种形式不能并存,
CI 报的是 'requested as both a version dep and a git dep'。

一次改依赖形式,要改的是**图里的每一处**,而例子也在图里。

* feat: declare the kernel-abi layer this package supplies

mcpp resolves the target side per layer after the dependency graph is known,
and reads which layer a package fills from its capabilities. Declaring
`mcpp:kernel-abi=openkal` states that this package implements the platform
interface a C library sits on, and that it answers to the name `openkal`.

The engine knows the three layer names and none of the implementations that
fill them, so nothing about openkal appears in mcpp for this to work.

Claude-Session: https://claude.ai/code/session_01Q4ucduLuSsETHYJ1RkGVVD

* chore: 0.1.1

The manifest states a capability the previous release did not, and the index
serves published tarballs rather than branches. A consumer resolving through
the index would otherwise get content in which this package declares no layer,
and the engine would resolve its target side to the compiler payload.

Claude-Session: https://claude.ai/code/session_01Q4ucduLuSsETHYJ1RkGVVD

---------

Co-authored-by: speak-agent <x.d2learn.org@gmail.com>

Author: Sunrisepeak

examples/hello/mcpp.toml

@@ -11,5 +11,5 @@ target  = "x86_64-windows-gnu"
 ldflags = ["-nostdlib", "-Wl,--subsystem,10", "-Wl,-e,efi_main"]
 
 [dependencies]
-openkal      = "0.5.1"
+openkal      = { git = "https://github.com/mcpplibs/openkal", branch = "feat/openkal-closure" }
 openkal-uefi = { path = "../.." }

mcpp.toml

@@ -15,14 +15,24 @@
 [package]
 namespace   = "mcpplibs"
 name        = "openkal-uefi"
-version     = "0.1.0"
+version     = "0.1.1"
 description = "An implementation of openkal on UEFI Boot Services, for applications the firmware loads before an operating system exists"
 license     = "Apache-2.0"
+
+# The layer this package supplies, in the vocabulary the engine resolves.
+#
+# `mcpp:kernel-abi` names the platform interface a C library sits on. On a
+# traditional stack that seam is unnamed — a C library issues system calls or
+# calls the platform's own entry points directly — and naming it is what lets
+# one C library sit above several platforms. `=openkal` is the interface this
+# package answers to; several packages answer to it and the engine knows none
+# of them by name.
+provides    = ["mcpp:kernel-abi=openkal"]
 authors     = ["mcpplibs"]
 repo        = "https://github.com/mcpplibs/openkal-uefi"
 
 [dependencies]
-openkal = "0.5.1"
+openkal = { git = "https://github.com/mcpplibs/openkal", branch = "feat/openkal-closure" }
 
 [build]
 flags = [