feat: add --sort and --reverse flags to bd search command

Added sorting capability to the search command, matching the behavior
already available in bd list. Supports sorting by: priority, created,
updated, closed, status, id, title, type, and assignee.

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

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

commands/search.md

@@ -33,6 +33,8 @@ Unlike `bd list`, which requires you to specify which field to search, `bd searc
 - **--label, -l**: Filter by labels (must have ALL specified labels)
 - **--label-any**: Filter by labels (must have AT LEAST ONE)
 - **--limit, -n**: Limit number of results (default: 50)
+- **--sort**: Sort by field: priority, created, updated, closed, status, id, title, type, assignee
+- **--reverse, -r**: Reverse sort order
 - **--long**: Show detailed multi-line output for each issue
 - **--json**: Output results in JSON format
 
@@ -62,6 +64,18 @@ bd search refactor --assignee alice --type task
 bd search bug --status open --limit 10
 ```
 
+### Sorted Output
+```bash
+# Search bugs sorted by priority (P0 first)
+bd search bug --sort priority
+
+# Search features sorted by most recently updated
+bd search feature --sort updated
+
+# Search issues sorted by priority, lowest first
+bd search refactor --sort priority --reverse
+```
+
 ### JSON Output
 ```bash
 # Get JSON results for programmatic use