bug: stale `crush` references in cmd/shellforge/main.go contradict v0.6 Goose migration

[jpleva91]

Bug

PR #70 updated all documentation to replace Crush with Goose as the primary local execution driver, but four stale Crush references remain in the Go source and are now contradicted by the updated docs.

Affected Lines (cmd/shellforge/main.go)

Line	Content	Type
94	Run a governed agent (claude, copilot, codex, gemini, crush)	CLI help text (shown to users)
519	fmt.Fprintln(os.Stderr, "Available drivers: claude, copilot, codex, gemini, crush")	Runtime error message
783	// Used by Crush fork to check actions before execution.	Code comment
809	// Map Crush tool names to ShellForge tool names	Code comment

Impact

• Users running shellforge run --help see crush as a valid driver
• Running shellforge run with an invalid driver shows crush as available option, misleading users who followed the updated docs
• Code comments imply cmdEvaluate is Crush-specific, obscuring that it is the generic evaluate endpoint now used by Goose via govern-shell.sh

Fix

1. Lines 94 and 519: replace crush with goose in the driver lists
2. Line 783: update comment to reflect govern-shell.sh / Goose usage
3. Line 809: update comment — no longer Crush-specific; this maps generic tool names

Related

• PR docs: post-v0.6 accuracy pass — Crush→Goose, arch update, bug backlog, godoc #70 — docs accuracy pass that triggered discovery of these mismatches