Add imperative feature bundles, intrinsic component sizing, and authoring timing logs

Generate state-backed atoms, interfaces, relationships and React/CSS packages
in a resumable command that prints the full source diff. Keep scaffold output
ordinary editable code. Shorten installed authoring guides while preserving
contracts and clarify historical design context.

Test generated bundles through immutable Nix verification and cover browser
isolation, nested sizing, interruption recovery, and command help.

src/capability-language/authoring-converge.ts

@@ -8,10 +8,17 @@ import { snapshotCommit } from "./checked-build.js";
 import { loadQuixosLock, parseQuixosLockDocument, formatQuixosLockDocument, retentionTagForCommit, type GitSource } from "../resource-lock/index.js";
 
 const execFile = promisify(callback);
-const command = async (cwd: string, executable: string, args: string[]) => (await execFile(executable, args, {
-  cwd, maxBuffer: 4 * 1024 * 1024,
-  env: { ...process.env, QUIXOS_JJ_NO_CHECKPOINT: "1", QUIXOS_SUBTREE_PUBLISH: "0", GIT_TERMINAL_PROMPT: "0" },
-})).stdout.trim();
+const command = async (cwd: string, executable: string, args: string[]) => {
+  const start = performance.now();
+  // Do not log arguments: transports may contain credentials. Source identities
+  // remain in the normal checked result, not in this timing channel.
+  const label = `${path.basename(cwd)} ${executable} ${args[0]}`;
+  try { return (await execFile(executable, args, {
+    cwd, maxBuffer: 4 * 1024 * 1024,
+    env: { ...process.env, QUIXOS_JJ_NO_CHECKPOINT: "1", QUIXOS_SUBTREE_PUBLISH: "0", GIT_TERMINAL_PROMPT: "0" },
+  })).stdout.trim(); }
+  finally { if (process.env.QUIXOS_TRACE_CAPTURE === "1") console.error(`[${new Date().toISOString()}] Capture: ${label}: ${Math.round(performance.now() - start)}ms`); }
+};
 const identity = (kind: string, repository: string) => `${kind}\0${repository}`;
 
 export type AuthoringBlocker = { directory: string; phase: "resolution" | "dependency" | "source" | "publication" | "concurrent-edit"; message: string };
@@ -92,7 +99,9 @@ export async function convergeAuthoring(start: string, target = "root") {
           } finally { await rm(temporary, { force: true }); }
         }
       }
+      const snapshotStarted = performance.now();
       const commit = await snapshotCommit(root);
+      if (process.env.QUIXOS_TRACE_CAPTURE === "1") console.error(`[${new Date().toISOString()}] Capture: ${directory} snapshot: ${Math.round(performance.now() - snapshotStarted)}ms`);
       phase = "publication";
       const ref = retentionTagForCommit(commit);
       const remote = await command(root, "git", ["ls-remote", "--refs", node.source.repository, ref]);