test: assertions for parse_readme_api (S2 Phase 1)

4 assertions: standard H3-pattern + no-API-section edge.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

init.lua

@@ -29,6 +29,34 @@ return M
         engine.test.equals(#empty.private, 0, "parse_lua_surface: empty source = no private")
     end
 
+    -- ===== parse_readme_api =====
+    do
+        local md = [[
+# lib-core.input
+
+Some abstract.
+
+## API
+
+### `input.bind(action_name, keys)`
+**Syntax:** `input.bind(action_name: string, keys: string[]) → void`
+
+### `input.is_action_down(action) → bool`
+Description.
+
+## Conventions
+Stuff.
+]]
+        local doc = api.parse_readme_api(md)
+        engine.test.equals(#doc.documented, 2, "parse_readme_api: 2 documented functions")
+        engine.test.equals(doc.documented[1], "bind", "parse_readme_api: first = bind")
+        engine.test.equals(doc.documented[2], "is_action_down", "parse_readme_api: second = is_action_down")
+
+        -- Edge: no API section
+        local no_api = api.parse_readme_api("# Just abstract\nNothing else.")
+        engine.test.equals(#no_api.documented, 0, "parse_readme_api: no API-section = empty")
+    end
+
     engine.exit(engine.test.failures())
 end