[h5v] :log command, :edit audit trail, :identity command

[gerchowl]

Parent: #161

Goal

Wire up the audit trail in h5v: :log to view history, :edit to create audited edits, :identity to manage identity.

Spec

:log command

• Display audit history in the attribute/info panel or a dedicated view
• Show entries newest-first, git-log style
• Scrollable if many entries

:edit with audit trail

• Existing :edit/:edit! commands now create audit entries
• Read identity from ~/.fd5/identity.toml
• Show confirmation with old → new value and identity before applying

:identity command

• :identity — show current identity
• :identity set <type> <id> <name> — save to ~/.fd5/identity.toml

TDD

• Test :log command parsing
• Test :identity command parsing
• Test edit creates audit entry via fd5 crate