fix: add git repo check to speckit-init

Author: michellejw

skills/speckit-init/SKILL.md

@@ -25,7 +25,19 @@ If `.specify/` exists:
 - Only create missing directories or files
 - Tell the user what was skipped and what was added
 
-### 2. Create directory structure
+### 2. Check for git
+
+Check if the project root has a git repository:
+```bash
+git rev-parse --git-dir 2>/dev/null
+```
+
+If no git repo exists, warn the user:
+> "No git repository detected. The speckit workflow uses feature branches (e.g., `001-feature-name`) for organizing specs. Consider running `git init` before creating features."
+
+Do NOT run `git init` automatically — that's the user's choice.
+
+### 3. Create directory structure
 
 ```
 .specify/
@@ -41,7 +53,7 @@ mkdir -p .specify/templates
 mkdir -p specs
 ```
 
-### 3. Copy templates from package
+### 4. Copy templates from package
 
 Copy all templates from the package into `.specify/templates/`. The package templates are at `../../templates/` relative to this SKILL.md.
 
@@ -56,20 +68,20 @@ Templates to copy:
 
 **Do NOT overwrite** existing templates. If a template already exists in `.specify/templates/`, skip it and note that it was preserved.
 
-### 4. Create roadmap
+### 5. Create roadmap
 
 If `.specify/roadmap.md` does not exist:
 - Copy `roadmap-template.md` from `.specify/templates/` to `.specify/roadmap.md`
 - Tell the user they can customize it with `/skill:speckit-roadmap`
 
-### 5. Offer constitution setup
+### 6. Offer constitution setup
 
 Ask the user: "Would you like to set up a project constitution now? This defines project-wide principles that guide all specs. (yes/no)"
 
 - If yes: copy `constitution-template.md` to `.specify/memory/constitution.md` and then run the constitution workflow (same as `/skill:speckit-constitution`) to fill in the placeholders
 - If no: skip, mention they can run `/skill:speckit-constitution` later
 
-### 6. Report
+### 7. Report
 
 Summarize what was created:
 ```