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

@@ -2017,28 +2017,21 @@ export function companySkillService(db: Db) {
     }
 
     // Re-scan GitHub/sks_sh sources to pick up newly added skills
-    const existingSkills = acceptedSkills;
-    const sourceByLocator = new Map<string, CompanySkill[]>();
-    for (const skill of existingSkills) {
+    const sourceLocators = new Set<string>();
+    for (const skill of acceptedSkills) {
       if (skill.sourceType !== "github" && skill.sourceType !== "skills_sh") continue;
       const locator = skill.sourceLocator ?? "";
-      if (!locator) continue;
-      if (!sourceByLocator.has(locator)) sourceByLocator.set(locator, []);
-      sourceByLocator.get(locator)!.push(skill);
+      if (locator) sourceLocators.add(locator);
     }
-    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 (!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);
-            }
+          if (acceptedSkills.some((s) => s.slug === nextSkill.slug)) continue;
+          const persisted = (await upsertImportedSkills(companyId, [nextSkill]))[0];
+          if (persisted) {
+            imported.push(persisted);
+            upsertAcceptedSkill(persisted);
           }
         }
       } catch {