/specforge:implement — build it, under the gate

Execute tasks.md top-to-bottom to implement the active feature. This is deliberately user-invoked only (not auto-triggered) so building is an explicit decision. The PreToolUse gate will refuse code edits unless the feature's specify and plan are approved — so if you haven't approved yet, do that first.

When to use

• The user explicitly asks to implement/build the feature.
• Trigger: /specforge:implement.

Preconditions (checked first)

1. There is an active feature in specforge/state.md.
2. Its specify and plan rows read approved. If not, stop and tell the user to run /specforge:approve specify and /specforge:approve plan (or /specforge:quick for a trivial change). Do not attempt to edit code before this — the gate will block it anyway.