Give bots skills: runbooks they load when a job matches

A skill is a runbook: a name, a unique slug, a one-line description of when
it applies, and the markdown body. A run only ever sees the slug and
description (one load_skill tool carries them), and reads the whole body
only when it calls the tool, so a long runbook costs nothing until needed.

Skills are the third extension kind beside MCP servers and custom tools, on
the same botExtensionsSql path, so per-bot, per-workspace and all-bots
grants work the same way, and attachDefaultExtensions hands an every-bot
skill to new bots. load_skill is a reserved tool name, so a custom tool
cannot shadow it, and a built-in wins a clash.

Managed on Settings > Skills; ExtensionRow links each kind to its own page
and a skill never reports a failure, since nothing connects or runs.

src/functions/backend/db/extensions/grab-skills-overview.ts

@@ -0,0 +1,34 @@
+import BunSQLite from "@moduletrace/bun-sqlite";
+import type { BUN_SQLITE_COBBLE_SKILLS } from "@/db/types/db";
+import type { SkillsOverviewPayload } from "@/src/types";
+import grabCrewRole from "../access/grab-crew-role";
+import grabExtensionAccess from "./grab-extension-access";
+import grabExtensionTargets from "./grab-extension-targets";
+import parseSkillRow from "./parse-skill-row";
+
+type Params = {
+    user_id: number | string;
+};
+
+/**
+ * The Skills settings page: every skill with who gets it, and what it can
+ * be attached to. A skill holds nothing secret, so admins read it too;
+ * only a super admin adds, edits or deletes.
+ */
+export default async function grabSkillsOverview({ user_id }: Params): Promise<SkillsOverviewPayload> {
+    const role = await grabCrewRole({ user_id });
+    const [rows, access, targets] = await Promise.all([
+        BunSQLite.sql<BUN_SQLITE_COBBLE_SKILLS>({ sql: `SELECT * FROM skills ORDER BY name COLLATE NOCASE ASC, id ASC` }),
+        grabExtensionAccess({ kind: "skill" }),
+        grabExtensionTargets({ role }),
+    ]);
+
+    return {
+        ...targets,
+        skills: (rows.payload || []).map((row) => {
+            const { all_bots, ...skill } = parseSkillRow({ row });
+
+            return { ...skill, access: { all_bots, ...access(skill.id) } };
+        }),
+    };
+}