Tune faction GUI sizing for Auto scale (tabs + map)

[plan3t]

Motivation

• The Factions UI was visually oversized under the Auto GUI scale and tab labels/buttons could overflow or look misaligned. The change intends to tighten sizes so controls and the map fit better on compact/large resolutions.
• The tab centering math included an extra trailing gap which caused tabs to be offset on many widths and scaling modes.

Description

• Reduced tab/button footprint by lowering TAB_BUTTON_WIDTH, TAB_BUTTON_HEIGHT, MIN_TAB_BUTTON_WIDTH, TAB_BUTTON_GAP, PANEL_CONTENT_WIDTH and minimum panel width in FactionMainScreen to make top tabs and controls more compact.
• Fixed tab centering by computing totalTabWidth = tabCount * tabButtonWidth + (tabCount - 1) * TAB_BUTTON_GAP and using that to center the tab row.
• Added runtime panel scaling by introducing panelContentWidth, horizontalScale, and helper methods scaledWidth(int) and panelX(int) to scale control widths/positions consistently, and converted many hardcoded control sizes/offsets to use those helpers.
• Added small member-section toggle buttons and layout helpers (membersSectionButton, invitesSectionButton, layoutMemberSectionButtons, updateMemberSectionButtonState) and a MemberSection enum to allow compact members/invites UI inside the Members tab.
• Refactored visibility handling to helper methods setButtonVisible(Button, boolean) and setEditBoxVisible(EditBox, boolean) and adjusted dynamic visibility logic to account for the new member section state.
• Reduced faction map footprint in FactionMapRenderer by tightening the map width/height budget and lowering cellSize bounds so the grid renders smaller and fits better at Auto scale.
• Added compact tab labels via FactionTab changes (new compactLabel and getCompactLabel()), and use compact labels when tabButtonWidth < TAB_COMPACT_LABEL_THRESHOLD.

Testing

• Ran ./gradlew compileJava and the build completed successfully.
• No automated GUI tests were present; changes were limited to layout constants, helper functions, and rendering math so compilation success is the validation performed.

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Codex Task