rs_investigate — moving through the ship and its people

The investigation half of Red String Over the Atlantic: standing in one of the six stations aboard LZ-114 Weltmeer, reading the deck plan, taking what a room will give you, sitting down with the people aboard, spending the hours the crossing allows, and turning the leg when they run out.

It owns the investigate phase, the rs.room and rs.dialogue screens, and the camera while the player is standing somewhere. It decides nothing about what a piece of evidence means — rs_rules owns the claims, the contradiction rule and the verifier, and this module asks it.

Using it

local Inv = Core.need("investigate")   -- nil until the slice has installed

Inv.begin()                 -- take the glass; enters Core.PHASES.investigate
Inv.goTo("promenade")       -- stand somewhere else; free, and moves the camera
Inv.examine("hs_prom_ledge")-- take what a hotspot holds; one hour
Inv.interview("vaudrey")    -- sit down with somebody; one hour buys the sitting
Inv.press()                 -- reveal the next exchange in that sitting; free
Inv.closeSitting()
Inv.openPlan() / Inv.closePlan()
Inv.advanceLeg()            -- the crossing goes on: new evidence, some of it stale
Inv.staleHeld()             -- the ids in hand that will no longer hold a string
Inv.toBoard()               -- hand off to rs_board, if it has landed
Inv.suspend()               -- give the glass back
Inv.snapshot()              -- everything above, as one readable table

Inv.examine and Inv.interview return (ok, cardIdOrReason). A refusal is always a sentence a player can read: already taken, no actions left, Dr. Felix Soltau is in cabin12, not available on leg 3.

The economy

Moving costs nothing. Examining a hotspot costs one action; so does sitting down with somebody, and that one hour buys the whole sitting however many times you press the point. When the hours run out the room offers only the leg turn, and crossing it refills the budget from Core.legs[n].actions, opens whatever the next leg makes available, and lets some of what you are carrying go stale.

What the module holds

What it asks of other slices

• rs_rules — card(id), availableAt(leg, station), isStale(id, leg) and, if it has one, advanceLeg(). All optional: with rules absent the module falls back to the geography and catalogue in casefile.luau, which carries no claims, because a claim nobody verifies is a lie.
• rs_dossier — Core.art.evidence(id) and Core.art.portrait(person). Absent art falls back to a drawn glyph and a drawn silver-gelatin portrait.
• rs_board — the corkboard tab in Cabin 7 hands over to it and says so plainly when it is not aboard yet.

Nothing here writes outside Core.state's investigation fields (station, actions, leg, held, seen) and its own two screens.