docs: use named arguments in the agent-docs examples and fix the 4.1 job examples

[bpamiri]

Docs-only. Two corrections to shown-to-users examples:

• The .ai agent-docs (and their byte-identical docs/consumer-ai/.ai/ mirrors) now use named arguments — afterCommit(methods="…", on="…") and .resources(name="products", except="delete") — matching the framework's "don't mix positional and named arguments" rule.
• The 4.1 background-job examples call queueStats() on a variable receiver (worker = new wheels.Job(); worker.queueStats()) instead of (new wheels.Job()).queueStats(), which doesn't compile on Adobe CF.

No runtime/framework code changes. The two .ai mirror copies stay byte-identical (consumer-docs check passes).

[bpamiri]

Review: head 84db2ba. APPROVE (docs).

• afterCommit("enqueueSearchIndex", on=...) → afterCommit(methods="enqueueSearchIndex", on=...), which matches afterCommit(string methods, string on) in model/callbacks.cfm.
• .resources("products", except="delete") → .resources(name="products", except="delete"), which matches resources(required string name, ...) in mapper/resources.cfc.
• Both edits are made identically in docs/consumer-ai/.ai and cli/lucli/templates/app/.ai, so the copies stay byte-identical. These were the only mixed positional/named Wheels calls in those trees.
• v4.1 background-jobs.mdx: all three (new wheels.Job()).queueStats() calls now use a variable receiver, which compiles on Adobe CF. Nothing else changed.
• Cosmetic, not blocking: the variable is worker here and jobs in the 4.2 guide (docs(web): use a variable receiver for wheels.Job in the 4.2 job examples #4458), and the trailing // comments in "queue health" no longer line up.

The final follows PR CI.

[bpamiri]

FINAL: APPROVE. Head 84db2ba.

• Docs only, 5 files: named arguments (afterCommit(methods=...), .resources(name=...)) in both .ai trees, which stay byte-identical, plus the variable-receiver rewrite in the v4.1 job examples. Unchanged since review.
• PR CI: 24 pass, 0 fail, 0 pending, 2 skipping (consumer-docs sync and the guides build included).