fix: tell a hands-off run its await gates are unavailable (#1234)

[suleimansh]

Closes #1234

Send an ambiguous prompt to a Run on: Claude web session and our own system prompt tells it to showChoices and AWAIT. It obeys, parks on a question, and the session is spent: nothing local can answer it (see #1234 for why every read/write route is closed).

This is the interim fix the issue settled on, worded as availability per the OP:

• new prompts/protocols/hands_off.md, composed by composeRunSystem right after the await protocol it amends, only when Driver.handsOff is set (fix(the-framework): end a Claude web run at the hand-off (#1225) #1231). It covers all four await gates, tells the agent to take the most plausible reading, state the assumption in one line, and carry on. Non-blocking blocks are unaffected, and prompts/system_prompt.md is untouched, so the System prompt #326 byte guard does not move.
• wired through both assembly paths (run.ts and prompt-run.ts) so they cannot drift (System prompt: clean internal architecture + unit tests #501).
• tests: block absent by default, present and ordered after the await protocol for a hands-off run, survives --vanilla, dies under transparent; plus a run-level test through runFramework with a hands-off driver.

The long-term shape (gates as per-session capabilities, and the #1237 bridge answering the questions that still happen) stays as discussed on the issue; this block deletes itself cleanly once that lands.

Note: check:prompt-drift currently fails on main over the ANLYSIS/ANALYSIS rename (repo commit 63095ae vs the #326 issue body); unrelated to this PR.