fix(skills): simplify source locator collection; remove redundant key derivation

- Use Set<string> instead of Map for tracking unique source locators
- Remove dead skillsAtSource destructuring from loop
- Remove redundant deriveCanonicalSkillKey call (already set by readUrlSkillImports)
- Invert slug check to continue guard for cleaner flow

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/services/company-skills.ts

@@ -2017,30 +2017,23 @@ export function companySkillService(db: Db) {
     }
 
     // Re-scan GitHub/sks_sh sources to pick up newly added skills
-    const existingSkills = acceptedSkills;
+    const sourceLocators = new Set<string>();
-    const sourceByLocator = new Map<string, CompanySkill[]>();
+    for (const skill of acceptedSkills) {
-    for (const skill of existingSkills) {
       if (skill.sourceType !== "github" && skill.sourceType !== "skills_sh") continue;
       const locator = skill.sourceLocator ?? "";
-      if (!locator) continue;
+      if (locator) sourceLocators.add(locator);
-      if (!sourceByLocator.has(locator)) sourceByLocator.set(locator, []);
-      sourceByLocator.get(locator)!.push(skill);
     }
-    for (const [sourceLocator, skillsAtSource] of sourceByLocator) {
+    for (const sourceLocator of sourceLocators) {
       try {
         const result = await readUrlSkillImports(companyId, sourceLocator, null);
         for (const nextSkill of result.skills) {
-          const existing = acceptedSkills.find((s) => s.slug === nextSkill.slug);
+          if (acceptedSkills.some((s) => s.slug === nextSkill.slug)) continue;
-          if (!existing) {
-            // New skill discovered — derive key and upsert
-            nextSkill.key = deriveCanonicalSkillKey(companyId, nextSkill);
           const persisted = (await upsertImportedSkills(companyId, [nextSkill]))[0];
           if (persisted) {
             imported.push(persisted);
             upsertAcceptedSkill(persisted);
           }
         }
-        }
       } catch {
         // Best-effort: don't fail the whole scan if one source fails
         warnings.push(`Could not re-scan source ${sourceLocator} — skipping.`);