Vertical slice part 1: tunable config, day/dusk/night clock, noise subsystem, lootable containers, inventory and hub stockpile

Motivation

This is part 1 of 3 of the Seminole playable vertical slice. It delivers the non-combat core systems that later parts build on: tunable config, the day/dusk/night clock, the noise system, looting into an inventory, and depositing into a hub stockpile. Parts 2 (canoe, weapons, infected) and 3 (night defense, barricades, full game flow and result) are separate proposals.

Constraints (confirmed by proposer)

• No compiler or CI in the sandbox. The maintainer compiles and runs the tests locally. Code must:
  • follow existing project patterns and UE 5.8 APIs exactly;
  • avoid uncommon or speculative engine APIs;
  • keep each change small and compile-safe.
• Placeholder content only. All content is C++ runtime-spawned placeholder primitives that extend the #22 test environment. No new .uasset maps, meshes, animations, audio or widget blueprints.
• Solo only.
  • No networking code or networking tests.
  • Where cheap, put authoritative state (clock phase, stockpile totals) in GameMode/GameState or world subsystems so later replication is not blocked.

Assumptions

• A1 Config: One UDeveloperSettings subclass (C++ defaults, editable in Project Settings) holds all tunables:
  • Day 480 s, Dusk 60 s.
  • Bow noise radius 500 uu, rifle noise radius 3000 uu. These are read by part 2.
  • Container search duration 2 s.
  • Supply amounts per container.
• A2 Clock end state: The clock runs Day → Dusk → Night and stops at Night. It broadcasts a phase-changed delegate and exposes ResetToDay(). Part 3 consumes this delegate for night defense and the Result state.
• A3 Noise listeners: Noise listeners implement a C++ interface (e.g. INoiseListener). Part 2's infected will implement it. In part 1, a simple placeholder listener actor or a test double verifies delivery.
• A4 HUD: The HUD is drawn with an AHUD Canvas in C++ to avoid widget assets.
• A5 Input: Interact uses the project's existing Enhanced Input setup.
  • If an Interact action exists, reuse it.
  • If not, add one following the #22 pattern.
  • If no asset-free path exists, document the manual step needed.
• A6 Supplies: Supply types are an enum {Food, Ammo, Materials} stored as integer counts.

Scope / Acceptance criteria

1. Config: A settings class exposes every value in A1. No gameplay code hard-codes these values.
2. Day clock:
   • A subsystem or GameState-owned clock advances automatically from game start: Day, then Dusk, then Night.
   • Each transition broadcasts a delegate with the new phase.
   • Time remaining in the current phase is queryable.
   • ResetToDay() restores Day with full duration.
   • The game starts in Day without console commands.
3. Lighting:
   • The test environment's directional light (and sky light, if present) intensity interpolates from day to dusk values.
   • Lighting reaches the night value at Night.
4. HUD:
   • Shows the current phase and time remaining.
   • Shows a visible dusk warning when Dusk begins.
   • Shows the player's carried supplies and the stockpile totals.
5. Noise system:
   • A world subsystem offers EmitNoise(Location, Radius, Instigator).
   • Only registered listeners within Radius (3D distance) receive the event, which includes location and instigator.
   • Listeners outside the radius do not receive it.
6. Inventory: A UActorComponent on the player pawn stores per-type supply counts, with add, remove and query functions.
7. Searchable containers:
   • At least 3 containers are spawned at a designated scavenging area in the test environment.
   • Interacting starts a timed search of the configured duration.
   • On completion the container grants its configured supplies to the interactor's inventory.
   • A searched container cannot be searched again and shows a visual change (e.g. a material or colour swap on the primitive).
8. Stockpile:
   • A stockpile actor is spawned at the hub.
   • Interacting transfers all carried supplies into the stockpile, leaving inventory at zero.
   • Stockpile totals live in authoritative state (GameState or the stockpile actor).
   • A spend function (e.g. TrySpend(Materials, N)) returns false without changing totals if the stockpile is insufficient. This is for part 3.
9. Tests: IMPLEMENT_SIMPLE_AUTOMATION_TEST (or the project's existing test pattern) covers:
   • Noise filtering: a listener inside the radius receives the event; one outside does not.
   • Clock transitions: Day → Dusk → Night fire in order with correct durations (time advanced deterministically, not in real time); reset returns to Day.
   • Loot flow:
     • container search grants supplies;
     • a second search grants nothing;
     • stockpile deposit moves totals and empties inventory;
     • TrySpend succeeds and fails correctly.
10. Docs:
    • ARCHITECTURE.md and/or a new ADR describe the config, clock, noise, inventory, container and stockpile systems and their extension points for parts 2 and 3.
    • Docs explain how to try the slice in the editor.
11. Manual verification list: The PR description lists everything the maintainer must verify manually: compile, test run, input binding, lighting.
12. No regressions: Code is written to compile cleanly, and existing tests are not modified except where required.

Out of scope

• Canoe, weapons, infected AI (part 2).
• Night defense waves, barricades, repair, win/lose, Result state and restart (part 3).
• Co-op/networking.
• Save/load.
• New binary assets.
• Art, audio and polish.