chore: initial project setup with agent guide

.agent/skills/gsd-remove-workspace/SKILL.md

@@ -0,0 +1,22 @@
+---
+name: gsd-remove-workspace
+description: Remove a GSD workspace and clean up worktrees
+---
+
+<context>
+**Arguments:**
+- `<workspace-name>` (required) — Name of the workspace to remove
+</context>
+
+<objective>
+Remove a workspace directory after confirmation. For worktree strategy, runs `git worktree remove` for each member repo first. Refuses if any repo has uncommitted changes.
+</objective>
+
+<execution_context>
+@.agent/get-shit-done/workflows/remove-workspace.md
+@.agent/get-shit-done/references/ui-brand.md
+</execution_context>
+
+<process>
+Execute the remove-workspace workflow from @.agent/get-shit-done/workflows/remove-workspace.md end-to-end.
+</process>