Add native Windows support (#91)

- Native Windows daemon using TCP loopback endpoints
- Direct-mode fallback for CLI/daemon compatibility
- Comment operations over RPC
- PowerShell installer script
- Go 1.24 requirement
- Cross-OS testing documented

Co-authored-by: danshapiro <danshapiro@users.noreply.github.com>
Amp-Thread-ID: https://ampcode.com/threads/T-c6230265-055f-4af1-9712-4481061886db
Co-authored-by: Amp <amp@ampcode.com>

cmd/bd/markdown_test.go

@@ -149,7 +149,7 @@ Just a title and description.
 				{
 					Title:       "Minimal Issue",
 					Description: "Just a title and description.",
-					Priority:    2,    // default
+					Priority:    2,      // default
 					IssueType:   "task", // default
 				},
 			},