feat: add mix eiseron.strip_comments (Sourceror); release v0.1.1

* Add mix eiseron.strip_comments (Sourceror); release v0.1.1

Token-aware Elixir comment stripper: removes # line comments while
preserving @moduledoc/@doc, heredocs, and ~H/~S sigils (a # inside a
string is never mistaken for a comment). Intended for cleaning generated
boilerplate (mix phx.new) to the eiseron no-comments standard.

Adds {:sourceror, ~> 1.0}. Covered by unit tests (full-line + inline
comments, heredoc/string/doc preservation). Bump VERSION to 0.1.1.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Co-authored-by: Guilherme Isaías Silva <guilherme@eiseron.com>

feat: scaffold eiseron_devtools meta-package

Provides :eiseron_credo_checks, :sobelow, and :mix_audit as transitive
deps via a single {:eiseron_devtools, only: [:dev, :test], runtime: false}
declaration. Also ships Mix.Tasks.Eiseron.Install to bootstrap .credo.exs
and print the precommit alias checklist.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>