Version bump to 0.20.1: Hash-based IDs

- Bump version across all components (CLI, plugin, MCP server)
- Update CHANGELOG.md with comprehensive hash ID migration notes
- Replace critical multi-clone warning with hash ID announcement
- Add Hash-Based Issue IDs section to README with:
  - ID format explanation (4/5/6 char progressive scaling)
  - Why hash IDs solve collision issues
  - Birthday paradox collision probability math
  - Migration instructions
- Update all examples to use hash IDs (bd-a1b2) instead of sequential (bd-1)

Breaking changes:
- Sequential ID generation removed (bd-c7af, bd-8e05, bd-4c74)
- issue_counters table removed from schema
- --resolve-collisions flag removed (no longer needed)

Migration: Run 'bd migrate' to upgrade database schema
Amp-Thread-ID: https://ampcode.com/threads/T-0b000145-350a-4dfe-a3f1-67d4d52a6717
Co-authored-by: Amp <amp@ampcode.com>

integrations/beads-mcp/pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "beads-mcp"
-version = "0.20.0"
+version = "0.20.1"
 description = "MCP server for beads issue tracker."
 readme = "README.md"
 requires-python = ">=3.10"

integrations/beads-mcp/src/beads_mcp/__init__.py

@@ -4,4 +4,4 @@ This package provides an MCP (Model Context Protocol) server that exposes
 beads (bd) issue tracker functionality to MCP Clients.
 """
 
-__version__ = "0.20.0"
+__version__ = "0.20.1"