chore: Bump version to 0.30.4

Updated all component versions:
- bd CLI: 0.30.3 → 0.30.4
- Plugin: 0.30.3 → 0.30.4
- MCP server: 0.30.3 → 0.30.4
- npm package: 0.30.3 → 0.30.4

New features:
- bd template instantiate for YAML workflow templates
- --assignee flag for template instantiation
- Fixed mail inbox --identity filtering
- Fixed orphan detection false positives

Note: Graph link edges (relates_to, replies_to, etc.) and mail commands
are experimental and subject to breaking changes.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

cmd/bd/info.go

@@ -287,6 +287,17 @@ type VersionChange struct {
 
 // versionChanges contains agent-actionable changes for recent versions
 var versionChanges = []VersionChange{
+	{
+		Version: "0.30.4",
+		Date:    "2025-12-18",
+		Changes: []string{
+			"bd template instantiate (bd-r6a.2) - Create beads issues from YAML workflow templates",
+			"--assignee flag for template instantiate - Auto-assign during instantiation",
+			"bd mail inbox --identity fix - Now properly filters by identity parameter",
+			"Orphan detection fixes - No longer warns about closed issues or tombstones",
+			"EXPERIMENTAL: Graph link fields (relates_to, replies_to, duplicate_of, superseded_by) and mail commands are subject to breaking changes",
+		},
+	},
 	{
 		Version: "0.30.3",
 		Date:    "2025-12-17",