G1000: two-way sim sync, more PFD/MFD fidelity, authentic dialogs

Sync (FlyWithLua companions in plugins/ + server/fmssync.js):
- FMS flight-plan two-way sync (App <-> in-sim FMS) via fms-sync.lua
- G1000 UI-state publish (page/range/inset) via ui-sync.lua + CDI source,
  baro, map-range follow
- Terrain awareness: elevation grid probe (terrain-probe.lua) -> red/yellow
  MFD overlay vs aircraft altitude

PFD:
- AFCS mode annunciation bar from autopilot _status datarefs
- CDI source GPS/VLOC colouring, BRG1/BRG2 pointers + DME windows, marker beacons
- magenta speed/altitude trend vectors, selected-altitude alerting
- time-based (frame-rate-independent) smoothing for attitude/heading/tapes

MFD:
- nav data bar (DTK/ETE/active leg), airways overlay from earth_awy.dat,
  compass rose anchored to the ownship

Dialogs (NEAREST/FLIGHTPLAN/DIRECT-TO/PROCEDURES):
- flat, square, embedded G1000 look (no shadow/rounded/transparency)
- compact lower-right placement, no close X (softkey toggles), single window
- NEAREST 2-line entries (ILS/VFR, COM freq, runway length), PROC action menu

Service worker: network-first HTML so reloads pick up new builds (cache v2).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

plugins/fms-sync.lua

@@ -0,0 +1,113 @@
+-- ============================================================================
+-- X-Plane Glass Cockpit  —  FMS two-way sync  (FlyWithLua companion)
+-- ============================================================================
+-- The web cockpit's bridge can't write the FMS via X-Plane's Web API. This
+-- script runs INSIDE X-Plane (FlyWithLua) and has the FMS SDK, so it bridges
+-- the shared plan <-> the in-sim FMS through two text files:
+--
+--   <X-Plane>/Output/fms-sync/to_sim.txt    written by the bridge (our plan)
+--   <X-Plane>/Output/fms-sync/from_sim.txt  written here (the sim's plan)
+--
+-- A 3-decimal lat/lon signature de-dupes both sides so they never loop.
+--
+-- INSTALL: copy this file to  <X-Plane>/Resources/plugins/FlyWithLua/Scripts/
+--          (install FlyWithLua NG+ first), then restart X-Plane or run
+--          "FlyWithLua > Reload all Lua script files".
+-- ============================================================================
+
+local SYNC   = SYSTEM_DIRECTORY .. "Output/fms-sync/"
+local TO_SIM   = SYNC .. "to_sim.txt"
+local FROM_SIM = SYNC .. "from_sim.txt"
+local last_sig = nil
+
+-- make sure the folder exists (bridge also creates it)
+os.execute('mkdir -p "' .. SYNC .. '" 2>/dev/null || mkdir "' .. SYNC .. '" 2>nul')
+
+-- 3-decimal lat/lon signature of a waypoint list ---------------------------
+local function sig_of(wps)
+  local parts = {}
+  for i = 1, #wps do
+    parts[i] = string.format("%.3f,%.3f", wps[i].lat, wps[i].lon)
+  end
+  return table.concat(parts, ";")
+end
+
+local function read_file(p)
+  local f = io.open(p, "r"); if not f then return nil end
+  local s = f:read("*a"); f:close(); return s
+end
+
+local function write_file(p, s)
+  local f = io.open(p, "w"); if not f then return end
+  f:write(s); f:close()
+end
+
+-- parse the bridge file: skip "# sig" lines, take "lat lon alt id type" ------
+local function parse(txt)
+  local wps = {}
+  if not txt then return wps end
+  for line in txt:gmatch("[^\r\n]+") do
+    if line:sub(1, 1) ~= "#" then
+      local lat, lon, alt, id = line:match("^%s*(-?%d+%.?%d*)%s+(-?%d+%.?%d*)%s+(-?%d+)%s+(%S+)")
+      if lat and lon then
+        wps[#wps + 1] = { lat = tonumber(lat), lon = tonumber(lon), alt = tonumber(alt) or 0, id = id or "WPT" }
+      end
+    end
+  end
+  return wps
+end
+
+-- read the current in-sim FMS plan ------------------------------------------
+local function read_fms()
+  local wps = {}
+  local n = XPLMCountFMSEntries()
+  for i = 0, n - 1 do
+    -- FlyWithLua: type, id, ref, altitude, lat, lon
+    local _t, id, _ref, alt, lat, lon = XPLMGetFMSEntryInfo(i)
+    if lat and lon and (math.abs(lat) > 0.0001 or math.abs(lon) > 0.0001) then
+      wps[#wps + 1] = { lat = lat, lon = lon, alt = alt or 0, id = (id ~= "" and id) or "WPT" }
+    end
+  end
+  return wps
+end
+
+-- write our plan into the in-sim FMS ----------------------------------------
+local function apply_to_fms(wps)
+  local old = XPLMCountFMSEntries()
+  for i = 1, #wps do
+    -- lat/lon entries keep our exact coords -> stable round-trip (no drift)
+    XPLMSetFMSEntryLatLon(i - 1, wps[i].lat, wps[i].lon, math.floor(wps[i].alt or 0))
+  end
+  for i = old - 1, #wps, -1 do XPLMClearFMSEntry(i) end  -- trim leftovers
+  if #wps >= 1 then
+    XPLMSetDisplayedFMSEntry(0)
+    XPLMSetDestinationFMSEntry(#wps - 1)
+  end
+end
+
+local function serialize(wps)
+  local lines = { "# " .. sig_of(wps) }
+  for i = 1, #wps do
+    lines[#lines + 1] = string.format("%.6f %.6f %d %s WPT", wps[i].lat, wps[i].lon, math.floor(wps[i].alt or 0), wps[i].id)
+  end
+  return table.concat(lines, "\n") .. "\n"
+end
+
+-- main loop (~1×/sec): whichever side differs from the agreed plan wins ------
+function fms_sync_tick()
+  local to_wps = parse(read_file(TO_SIM))
+  local tsig   = sig_of(to_wps)
+  local fm_wps = read_fms()
+  local fsig   = sig_of(fm_wps)
+
+  if tsig ~= "" and tsig ~= last_sig then
+    apply_to_fms(to_wps)            -- App -> Sim
+    last_sig = tsig
+  elseif fsig ~= last_sig then
+    write_file(FROM_SIM, serialize(fm_wps))  -- Sim -> App
+    last_sig = fsig
+  end
+end
+
+do_often("fms_sync_tick()")
+logMsg("[glass-cockpit] FMS sync active -> " .. SYNC)