ShellSyntaxTree 0.3.0-alpha.1

This prerelease refreshes the Netclaw validation package with the Bash
redirect and command-resolution slices completed after 0.3.0-alpha. It does
not change the public v0.3 API surface, and the conservative v0.2 projection
remains available.

Added

• Added bounded Bash heredoc analysis with explicit delimiter, body, expansion,
  tab-stripping, completeness, and substitution facts.
• Added Bash <<< here-string analysis. Exact and finite data include Bash's
  trailing newline, remain non-path, and preserve independently executable
  substitutions as command occurrences.

Security and compatibility

• Reject command-resolution mutation through unsupported exec, hash,
  alias, shell-option, builtin-enable, and reserved execution forms before a
  later occurrence can inherit an unsafe executable identity.
• Keep unknown here-string values structurally visible without guessing their
  data, and fail malformed redirect forms atomically.
• Pin the unchanged public API with reflection, equality, hashing, string, and
  unknown-enum compatibility tests, and document occurrence-first consumer
  authorization.