[S0ly]

Stacked PRs, merge in this order: #508 → #509 → #507 → #511 → #510
Until the ones before it are merged, this diff also includes them.

Only this PR's changes: changes since #508

Split into commits by area (theme and menus, HUD, diplomacy and chat, match setup, settings and text), so it can be reviewed one commit at a time. Only the last commit builds on its own.

• One dark theme matching the website and launcher, floating HUD cards

• Button is still the data model, ButtonCell only draws it; everything is plain GuiGraphics plus small helpers in ui/

• Observer is now Diplomacy and hides enemy info under fog

• Reworked match setup with fog of war and alliance lock toggles, host can close empty seats

• New settings menu and keys

• Compact chat panel and system messages

• Main menu: Discord button, tutorial button that generates the tutorial map, Realms removed, note in Multiplayer about the network launcher

• Text sizes that stay sharp: Silkscreen for small labels, the Minecraft font for body text and numbers

• Worker command card: commands on A-G, Basic / Advanced building tabs on Z / X, so build keys no longer move when garrison or return resources shows up

• Villagers show their profession head, an XP bar towards veteran and a passive explaining the bonus (villager XP is now synced to the client)

• Spectator HUD with every player's resources, and a match feed in their chat

• Surrender button in the Esc menu, victory / defeat banner, clearer lobby roster and ready button

• Every tooltip uses the HUD style; clock, training queue, resource bar and drag box restyled

• Bottom bar that's always there and splits on wide screens, new selection panel, portraits framed on the face

• Big map on M, satellite view on comma or by scrolling past max zoom, second column of map tools

• Sandbox tools moved to a tabbed dock on the right, with search and sorting

• Unit outlines work with Oculus/Iris, underlines no longer show through terrain

• Selection panel cleanup: smaller stats column, +N tile, empty panels hide, bigger slots

• Resource tooltips and hover text redone

• Satellite view shows unit items, opens after 0.5s of scrolling at max zoom

• Custom building menu cleanup