feat: initial blink-cmp-ssh implementation

Problem: the existing blink-cmp-sshconfig plugin uses a synchronous,
build-time Python scraping approach that requires uv and make to
generate a static Lua file.

Solution: implement a runtime, async blink.cmp source that parses
ssh_config keywords from man ssh_config and enum values from ssh -Q
queries, matching the architecture of blink-cmp-tmux and
blink-cmp-ghostty.

vim.toml

@@ -0,0 +1,33 @@
+[selene]
+base = "lua51"
+name = "vim"
+
+[vim]
+any = true
+
+[jit]
+any = true
+
+[bit]
+any = true
+
+[assert]
+any = true
+
+[describe]
+any = true
+
+[it]
+any = true
+
+[before_each]
+any = true
+
+[after_each]
+any = true
+
+[spy]
+any = true
+
+[stub]
+any = true