Put the keyboard shortcuts back on MapRoulette 3's keys

[CollinBeczak]

MR4 kept a shortcut registry but had inverted the ergonomics it existed for. Status changes — the one thing a mapper does on every task — sat on Ctrl/Cmd+F and Ctrl/Cmd+P, the two modifiers a browser already owns for Find and Print, while the bare left-hand keys a one-handed mapper can reach went to view toggles used once a session. Worse, f and d did view and selection things, so MR3 muscle memory produced the wrong action rather than none.

The statuses go back to f q x d w, the editors to e r t y v a, and the map to + - 0. Each opens the confirmation dialog rather than submitting, which is what makes a bare letter safe. h and l stay unbound: MR4 has no previous/next task control for them to shadow, and neither do s and o, whose task-feature and OSM-data layers do not exist here yet.

Three tiers now, with no exceptions: a bare letter acts on the task screen; Shift+letter is the "more" variant of its bare key; Ctrl/Cmd is for the two commands that must work while typing, search and submit. That leaves the MR4-only toggles on keys 3 never used — b/Shift+B for the bundle filter and lasso, m for markers, Shift+O for other challenges.

Around that:

• Key names come out of the translated strings and are composed at render time from the binding, so rebinding is no longer a change to 16 locale catalogs. They render as key caps in the map tooltips, the editor menu and the search box, which is where mappers look.
• The registry moves to the app root, so ? works everywhere and the global search key joins it instead of running its own listener.
• Dialogs suspend shortcuts while they hold the screen. Radix traps focus, but a bare letter still reached the window listener.
• Shortcuts register unconditionally and flip enabled, carrying the reason they are out of reach, so the dialog can say "start mapping this task first" instead of quietly omitting the row.
• Categories are ids rather than translated labels, which is what the dialog's ordering was comparing against — it only sorted in English.
• Matching, formatting and conflict detection move into a tested module, and duplicate bindings now warn in development instead of resolving by registration order.

The editor menu grew an "open in" section: the six editor keys had no visible control to shadow, since picking an editor there only set the default.