feat(FN-1216): rename extension tools to fn_* across CLI and docs

- Rename all pi extension tool registrations from kb_* to fn_* across task, mission, and agent tool families
- Update extension and skill-sync tests plus Fusion skill docs/workflows to assert and document the new fn_* tool names
- Align product-identity strings across core, dashboard, and CLI references, including GitHub import examples, User-Agent headers, and terminal TERM_PROGRAM
- Add a @gsxdsm/fusion minor changeset describing the extension tool-prefix rename

packages/dashboard/src/github.ts

@@ -1416,7 +1416,7 @@ export class GitHubClient {
     const headers: Record<string, string> = {
       Accept: "application/vnd.github+json",
       "X-GitHub-Api-Version": "2022-11-28",
-      "User-Agent": "kb-dashboard/1.0",
+      "User-Agent": "fn/1.0",
     };
 
     if (this.token) {
@@ -2006,7 +2006,7 @@ export class GitHubClient {
             Accept: "application/vnd.github+json",
             "X-GitHub-Api-Version": "2022-11-28",
             Authorization: `Bearer ${jwt}`,
-            "User-Agent": "kb-dashboard/1.0",
+            "User-Agent": "fn/1.0",
           },
         },
       );
@@ -2040,7 +2040,7 @@ export class GitHubClient {
             Accept: "application/vnd.github+json",
             "X-GitHub-Api-Version": "2022-11-28",
             Authorization: `Bearer ${installationToken}`,
-            "User-Agent": "kb-dashboard/1.0",
+            "User-Agent": "fn/1.0",
           },
         },
       );
@@ -2093,7 +2093,7 @@ export class GitHubClient {
             Accept: "application/vnd.github+json",
             "X-GitHub-Api-Version": "2022-11-28",
             Authorization: `Bearer ${installationToken}`,
-            "User-Agent": "kb-dashboard/1.0",
+            "User-Agent": "fn/1.0",
           },
         },
       );