feat: add includeSkills to HostConfig + update OpenClaw config

Add includeSkills allowlist field with union logic (include minus skip).
Update OpenClaw to generate only 4 native methodology skills (office-hours,
plan-ceo-review, investigate, retro). Remove staticFiles.SOUL.md reference
(pointed to non-existent file).

scripts/host-config.ts

@@ -62,6 +62,8 @@ export interface HostConfig {
     metadataFormat?: string | null;
     /** Skill directories to exclude from generation for this host. */
     skipSkills?: string[];
+    /** Skill directories to include (allowlist). Union logic: include minus skip. */
+    includeSkills?: string[];
   };
 
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