fix(pathfinding): added circular path detection and bail for wallhug

[cerwym]

Adds history and removes old 90 degree wallhug state logic with proper circular loop check

[Copilot]

Pull request overview

This PR updates the wallhug pathfinding logic to detect circular movement patterns (loops) using a short position history, replacing the previous “90-degree retry” wallhug state handling.

Changes:

• Add an 8-sample position history + counters to struct Navigation for loop detection.
• Introduce update_position_history() and check_for_circular_path() helpers in ariadne_wallhug.c.
• Replace the old wallhug retry/state logic with a “circular loop detected → flip wallhug side” bailout.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
src/ariadne_wallhug.c	Adds position-history tracking and loop detection; swaps out previous retry-based wallhug logic for loop-based bailout.
src/ariadne.h	Extends struct Navigation with loop-detection state (history buffer + indices/counters).

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[Copilot]

Adding fields to struct Navigation changes sizeof(struct CreatureControl) and therefore sizeof(struct Game) (since game_legacy.h embeds cctrl_data[]). The save loader (load_game_chunks) rejects saves when hdr.len != sizeof(struct Game), so this will make existing savegames incompatible. If preserving save compatibility matters, the save chunk needs a version bump and backward-compatible load path (or this needs to be explicitly documented as a breaking change).

Suggested change

unsigned char loop_counter;

[cerwym]

Working on prevention of save game breaks

[cerwym]

Put back in draft while working on avoiding save break

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

Comments suppressed due to low confidence (1)

src/ariadne_wallhug.c:134

• The doc comment says this function detects a "circular path", but the current implementation only checks whether the creature is within a fixed distance of any previous sample and increments a counter. That logic can also trigger for backtracking, small jitter, or being stationary, which isn't necessarily a circle. Either tighten the detection to match the comment (eg, detect repeated cycles with sufficient displacement), or update the comment to accurately describe the heuristic being used.

/// @brief Checks if the creature is moving in a circular path.
/// @param creatng The creature to check.
/// @return True if a circular path is detected, false otherwise.
static TbBool check_for_circular_path(struct Thing *creatng)

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