Bump Required Versions

Updates the minimum version constraints that this mthds-agent release enforces against:

• The Claude Code mthds plugin (when running inside Claude Code) — MIN_PLUGIN_VERSION in src/agent/plugin-version.ts.
• The pipelex PyPI package (provides both the pipelex and pipelex-agent binaries) — PIPELEX_PKG.version_constraint in src/agent/binaries.ts.
• The pipelex-tools PyPI package (provides the plxt binary) — PIPELEX_TOOLS_PKG.version_constraint in src/agent/binaries.ts.

The constants in those two files are the single source of truth. Tests import the constants directly, so bumping these values does not require test edits — the test suite re-exercises the new floor automatically.

Why each lives where it lives

• MIN_PLUGIN_VERSION enforces the opposite direction from the package constraints: the agent checks the plugin is recent enough. The plugin's own min_mthds_version (in mthds-plugins/targets/defaults.toml) enforces the agent is recent enough. Both versions get bumped on coordinated releases — but this skill only bumps the agent side. The plugin side has its own skill (bump-mthds-version in mthds-plugins).
• The BINARY_RECOVERY map keys binaries (pipelex, pipelex-agent, plxt), but each entry spreads a shared *_PKG constant. The package constants own the version constraint, so the pipelex and pipelex-agent binaries cannot drift apart even by accident — there is only one line to edit.

Workflow

1. Determine which targets to bump and to what