Make passable storage areas inspectable from their center

On the original tutorial map, a normally placed storage area cannot be inspected with Enter at its center. Selecting a blocked edge tile opens the same area's panel.

Reproduced with native browser controls on a61986b:

1. Build a storage area using the normal Misc. menu. The site in this playthrough is at (192,208).
2. Pause, select tile (192,208) using the map's keyboard controls and press Enter. No Selected building panel appears.
3. Move to (190,204), a blocked tile belonging to the same footprint, and press Enter. The Storage area panel appears, showing Builders are at work and construction progress.

The controller currently resolves inspection through the path-blocking building index plus the doorstep. The reference storage geometry leaves its center passable. Inspection should recognize the area without changing that path-blocking geometry. The pinned remake maintains a separate building-selection grid over the full protected area: MainGrid passes that region to ObjectsGrid. The storage XML includes its center as protected, passable ground. These sources identify the intended selectable region without an original-runtime claim.

Acceptance:

• Make storage centers and their intended interactive area selectable through both ordinary map clicks and keyboard Enter, during construction and after completion.
• Use an application-owned selection contract. Preserve passable storage ground, routing, ownership, fog and enemy-information boundaries.
• Cover a real storage session, another ordinary building, empty tiles, another player's building, save/reload and unchanged simulation state. Add real browser input coverage and repeat the original-map reproduction.
• Run relevant unit/browser checks, lint, types and the production build. Verify committed CI before closing this issue.

The original-map storage is still under construction in this capture. This report establishes the selection failure, not the cause of any separate construction delay. Related #86 and #4 remain open. Local JPEG and accessibility captures are retained; original-media images are not republished.

Storage areas now open their inspection panel from the passable center and the rest of their protected area. Keyboard Enter and pointer clicks use the same selection path, matching the supplied remake while preserving movement geometry and ownership boundaries.

The original tutorial-map reproduction passes. Tests also cover construction, completion, saves, a castle, empty ground and foreign buildings. All 354 unit tests and 472 browser checks pass, including the full rival battle. Implementation, validation details and passing CI.