fix: preserve tool names in prose

[EvanProgramming]

Fixes #137

Summary

• require sentence-boundary and bounded argument context before treating a known tool marker as an alias control
• preserve tool names, labels, explanations, and Unicode prose in final CLI replies and Web/SSE streams
• keep complete canonical aliases and fenced aliases executable while rejecting prose-shaped pseudo-actions

Validation

• focused CLI/parser and Web/SSE regressions
• make docs-check with an isolated SQLite path
• git diff --check