Create: RoadWorks

1. Multi-stage construction (Survival mode)

Before: The "Build" button wouldn't start if even a single block was missing (resulting in a "Missing blocks" message and no action). Also, running out of a specific block type mid-construction would halt the entire process immediately.

Now (RoadBuildManager.java):
- If blocks are missing at startup, construction begins anyway with a warning: "Missing blocks: 64x Stone, 12x Oak Planks — building what is possible; the rest will be ignored."
- During placement, if the supply of a specific block type runs out, that block is simply skipped (instead of stopping construction), while other block types continue to be placed. Once a block type is exhausted, it remains ignored for the rest of the pass to ensure predictable results.
- Upon completion: "Partial road: 8420 blocks placed, 312 missing (312x Stone). Gather the blocks and restart Build to continue."
- Clicking "Build" again resumes from where it left off: since the planner already ignores correctly placed blocks, only the missing section is built. Durability is consumed only for the blocks actually placed. Creative mode remains unchanged.

2. Settings saved per bridge type

- New `BridgeSettingsByMode.java`: A complete set of settings (pillar spacing, arch width/height, cables, pylons, etc.) for each mode (None / Viaduct / High Arch / Suspension). Adjusting a suspension bridge no longer affects viaduct settings.
- In the GUI, switching bridge modes reloads the sliders with the saved values ​​for that mode (the preset field text is preserved during reloading).
- Backward compatibility: Old items and presets (using flat JSON keys) still load correctly; their values ​​are applied to all modes as a starting point. The new presets save the entire map under the `bridge_settings` key, so a preset preserves the settings for all four bridge types.