fix(hotel_receptionist): room and dispute tool-flow fixes

[u9g]

Summary

Nine independent room- and dispute-tool fixes from #6567, split one per commit. Everything here is scoped to examples/hotel_receptionist/tools_rooms.py plus the Userdata fields two of the guards need.

Dispute flow

• dispute_charge took a bool for whether the caller had accepted the offer, but the agent has to call the tool to learn what the policy offer even is — so the first call filed the dispute and applied the waiver or credit before the caller had been told anything, and a declined second call could not undo it. The argument is now pending/accepted/declined: a pending call resolves the policy and hands back the offer to present, persisting nothing. Policies whose accepted and declined outcomes are identical are automatic and still resolve on the first call.
• An escalation reply that opened with "I've escalated this to the manager" skipped the stance the caller is owed from the record — a card-guaranteed no-show charge that stands, say — and read as a brush-off. The policy explanation comes first, and a callback number gets recorded rather than an unasked-for live transfer offered.
• lookup_invoice rendered a line as Room (2 nights) 560 dollars, so the model copied the merged label-plus-amount string into dispute_charge, the exact-label match failed, and the error told it to read the lines back — producing the same merged string again, looping until the caller gave up. Labels are quoted at the source, and the no-match error lists the exact labels and says what to do when the charge genuinely isn't on the invoice.
• "I thought I cancelled" reads as a cancellation, so the model picked cancellation_fee; that category is only for a fee from an actual recorded cancellation. The no_show line is now drawn in the arg docstring, where the choice is made.

Room tools

• A caller booking two rooms can get the model to call start_room_booking twice in one turn. Inline AgentTasks cannot run in parallel — the second activation supplants the first, whose function call then never resolves, and the session wedges. A second call now raises instead of running.
• When card capture ends with no usable card, the bare ToolError reached the model as a dead end and it left the caller thinking the reservation was at risk. Nothing was lost: the existing card stays on file and a working one isn't needed until check-in. The callback offer becomes the turn's question.
• The model sometimes re-invoked start_booking_modification with no new caller input instead of relaying the result, re-opening the flow on the booking it just updated while the confirmation and any refund never got spoken. Same guard the cancel path already has.
• The progressive-disclosure rule bled into lookup_booking, so a caller confirming their reservation heard only the field they named and never got the chance to catch a wrong room type or smoking status before arrival. That rule is now scoped to option lists.
• The walk plan told the agent to give it "in short pieces", which let it spread the four parts across turns — an angry guest hangs up before the later ones land, so they never hear that the taxi is covered or that their own room is theirs again. All four parts go out in one reply, and the walk is stated as the resolution so the agent stops offering a manager on top of it.

Not carried over from #6567

• describe_room_options in check_room_availability — fix(hotel_receptionist): hotel_db stored-state and read-back fixes #6805 already carries it.
• The dispute no-match error's load_capability("guest_services") became record_followup (kind="other"); capabilities.py isn't on main, so the original wording would name a nonexistent tool.

Testing

• ruff format --check and ruff check clean across examples/hotel_receptionist/.
• Smoke-checked the three-state resolution across all six DISPUTE_POLICIES actions: the two automatic actions (sub-threshold minibar, duplicate-charge ticket) still resolve on the first call; every other action returns an unfiled offer while pending, then the matching outcome on accepted/declined.
• mypy on the two changed files goes 13 -> 15 errors, all RoomToolsMixin has no attribute "session" — the pre-existing mixin pattern the cancel guard already trips, and examples/ is outside scripts/check_types.py's scope.

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no bugs or issues to report.