fix(skills): resolve {baseDir} placeholder in DB-backed skill content (#1145)

Both PG and SQLite skill stores returned SKILL.md content without the
{baseDir} substitution that skills.Loader.LoadSkill performs for
file-based access. Agents reading SKILL.md via this RPC saw the literal
placeholder, breaking script-invocation lines that expect absolute paths.

Mirror the loader's substitution in both store implementations so
behavior is consistent regardless of access path.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

internal/store/pg/skills_content.go

@@ -40,6 +40,11 @@ func (s *PGSkillStore) LoadSkill(ctx context.Context, name string) (string, bool
 	if err != nil {
 		return "", false
 	}
+	// Resolve {baseDir} placeholder so SKILL.md script-invocation lines hold
+	// absolute paths regardless of agent CWD. Mirrors skills.Loader.LoadSkill
+	// substitution; without it, agents reading SKILL.md via this RPC see the
+	// literal placeholder.
+	content = strings.ReplaceAll(content, "{baseDir}", info.BaseDir)
 	return content, true
 }
 

internal/store/sqlitestore/skills_content.go

@@ -35,6 +35,11 @@ func (s *SQLiteSkillStore) LoadSkill(ctx context.Context, name string) (string,
 	if err != nil {
 		return "", false
 	}
+	// Resolve {baseDir} placeholder so SKILL.md script-invocation lines hold
+	// absolute paths regardless of agent CWD. Mirrors skills.Loader.LoadSkill
+	// substitution; without it, agents reading SKILL.md via this RPC see the
+	// literal placeholder.
+	content = strings.ReplaceAll(content, "{baseDir}", info.BaseDir)
 	return content, true
 }