Removes three console scripts that should never have been declared at the
top-level shell namespace from hanzo-mcp:
hanzo-dev — name-collided with the canonical Rust Codex-fork CLI
at /opt/homebrew/bin/hanzo-dev (~/work/hanzo/dev).
hanzo-plugin — unscoped; if needed, belongs in its own package.
hanzo-unified — vague + unscoped.
Modules remain importable (hanzo_mcp.dev_tools, .cli_plugin,
.unified_backend) so any user-facing entry point can ship from its own
package later. Only hanzo-mcp + hanzo-mcp-dev stay as scripts here.
Also bumps the hanzo-tools-browser floor to >=0.5.5 so the CdpTool alias
(mcp__hanzo__cdp) is guaranteed alongside mcp__hanzo__browser on every
hanzo-mcp install.