coding-agent: change Pi skills to use SKILL.md convention

Breaking change: Pi skills must now be named SKILL.md inside a directory,
matching Codex CLI format. Previously any *.md file was treated as a skill.

Migrate by renaming ~/.pi/agent/skills/foo.md to ~/.pi/agent/skills/foo/SKILL.md

pi-mono.code-workspace

@@ -6,6 +6,12 @@
 		},
 		{
 			"path": "../../moms"
+		},
+		{
+			"path": "../../.pi/agent"
+		},
+		{
+			"path": "../pi-skills"
 		}
 	],
 	"settings": {}