feat(terminal): refactor runtime and add mobile workspace (#2280)

Replace the legacy terminal flow with a shared authenticated WebSocket
runtime used across web, desktop, relay, and mobile surfaces.

- introduce the v3 terminal protocol with scoped attachments, snapshots,
  ordered output, bounded replay history, reconnects, and explicit lifecycle
- harden PTY creation, restart, resize, close, force-kill, idle cleanup,
  shell selection, login mode, environment sanitization, and appearance sync
- add runtime-aware terminal APIs with relay authentication and Electron parity
- add a fullscreen mobile terminal workspace with touch scrolling,
  long-press selection, safe-area controls, quick keys, and Ctrl/Alt input
- add terminal selection attachments, preview detection, project actions,
  shell settings, and localized UI
- harden Ghostty rendering, resize recovery, Unicode handling, block
  characters, line height, and stale-row behavior
- remove the obsolete terminal SSE path and update reverse-proxy guidance
- expand terminal runtime, transport, input, selection, and store coverage
- avoid duplicate web builds when preparing mobile assets in root CI builds

patches/ghostty-web+0.4.0.patch

@@ -10,21 +10,58 @@ index 0000000000000000000000000000000000000000..11111111111111111111111111111111
 +    this.ctx = g, this.fontSize = B.fontSize ?? 15, this.fontFamily = B.fontFamily ?? "monospace", this.lineHeight = B.lineHeight ?? 1, this.cursorStyle = B.cursorStyle ?? "block", this.cursorBlink = B.cursorBlink ?? !1, this.theme = { ...f, ...B.theme }, this.devicePixelRatio = B.devicePixelRatio ?? window.devicePixelRatio ?? 1, this.palette = [
 @@ -1366,1 +1366,1 @@
 -    const g = B.measureText("M"), E = Math.ceil(g.width), C = g.actualBoundingBoxAscent || this.fontSize * 0.8, I = g.actualBoundingBoxDescent || this.fontSize * 0.2, D = Math.ceil(C + I) + 2, i = Math.ceil(C) + 1;
-+    const g = B.measureText("M"), E = Math.ceil(g.width), C = g.actualBoundingBoxAscent || this.fontSize * 0.8, I = g.actualBoundingBoxDescent || this.fontSize * 0.2, D0 = Math.ceil(C + I), extra = Math.max(0, Math.round((this.lineHeight - 1) * D0)), D = D0 + 2 + extra, i = Math.ceil(C) + 1;
++    const g = B.measureText("M"), E = Math.ceil(g.width), C = g.actualBoundingBoxAscent || this.fontSize * 0.8, I = g.actualBoundingBoxDescent || this.fontSize * 0.2, D0 = Math.ceil(C + I) + 2, extra = Math.max(0, Math.round((this.lineHeight - 1) * D0)), D = D0 + extra, i = Math.ceil(C) + 1;
 @@ -1538,1 +1538,1 @@
 -    if (A.grapheme_len > 0 && ((k = this.currentBuffer) != null && k.getGraphemeString) ? N = this.currentBuffer.getGraphemeString(g, B) : N = String.fromCodePoint(A.codepoint || 32), this.ctx.fillText(N, w, s), A.flags & e.FAINT && (this.ctx.globalAlpha = 1), A.flags & e.UNDERLINE) {
-+    if (A.grapheme_len > 0 && ((k = this.currentBuffer) != null && k.getGraphemeString) ? N = this.currentBuffer.getGraphemeString(g, B) : N = A.codepoint == null || A.codepoint <= 0 || A.codepoint > 1114111 || A.codepoint >= 55296 && A.codepoint <= 57343 ? " " : String.fromCodePoint(A.codepoint), this.ctx.fillText(N, w, s), A.flags & e.FAINT && (this.ctx.globalAlpha = 1), A.flags & e.UNDERLINE) {
-@@ -1780,1 +1780,1 @@
++    if (A.grapheme_len > 0 && ((k = this.currentBuffer) != null && k.getGraphemeString) ? N = this.currentBuffer.getGraphemeString(g, B) : N = A.codepoint == null || A.codepoint <= 0 || A.codepoint > 1114111 || A.codepoint >= 55296 && A.codepoint <= 57343 ? " " : String.fromCodePoint(A.codepoint), this.renderBlockChar(A.codepoint || 32, E, C, I) || this.ctx.fillText(N, w, s), A.flags & e.FAINT && (this.ctx.globalAlpha = 1), A.flags & e.UNDERLINE) {
+@@ -1557,1 +1557,36 @@
+   }
++  renderBlockChar(A, B, g, E) {
++    const C = this.metrics.height, I = E / 2, D = C / 2;
++    switch (A) {
++      case 9600: this.ctx.fillRect(B, g, E, D); return !0;
++      case 9601: this.ctx.fillRect(B, g + C * 7 / 8, E, C / 8); return !0;
++      case 9602: this.ctx.fillRect(B, g + C * 3 / 4, E, C / 4); return !0;
++      case 9603: this.ctx.fillRect(B, g + C * 5 / 8, E, C * 3 / 8); return !0;
++      case 9604: this.ctx.fillRect(B, g + D, E, D); return !0;
++      case 9605: this.ctx.fillRect(B, g + C * 3 / 8, E, C * 5 / 8); return !0;
++      case 9606: this.ctx.fillRect(B, g + C / 4, E, C * 3 / 4); return !0;
++      case 9607: this.ctx.fillRect(B, g + C / 8, E, C * 7 / 8); return !0;
++      case 9608: this.ctx.fillRect(B, g, E, C); return !0;
++      case 9609: this.ctx.fillRect(B, g, E * 7 / 8, C); return !0;
++      case 9610: this.ctx.fillRect(B, g, E * 3 / 4, C); return !0;
++      case 9611: this.ctx.fillRect(B, g, E * 5 / 8, C); return !0;
++      case 9612: this.ctx.fillRect(B, g, I, C); return !0;
++      case 9613: this.ctx.fillRect(B, g, E * 3 / 8, C); return !0;
++      case 9614: this.ctx.fillRect(B, g, E / 4, C); return !0;
++      case 9615: this.ctx.fillRect(B, g, E / 8, C); return !0;
++      case 9616: this.ctx.fillRect(B + I, g, I, C); return !0;
++      case 9620: this.ctx.fillRect(B, g, E, C / 8); return !0;
++      case 9621: this.ctx.fillRect(B + E * 7 / 8, g, E / 8, C); return !0;
++      case 9622: this.ctx.fillRect(B, g + D, I, D); return !0;
++      case 9623: this.ctx.fillRect(B + I, g + D, I, D); return !0;
++      case 9624: this.ctx.fillRect(B, g, I, D); return !0;
++      case 9625: this.ctx.fillRect(B, g, I, C); this.ctx.fillRect(B + I, g + D, I, D); return !0;
++      case 9626: this.ctx.fillRect(B, g, I, D); this.ctx.fillRect(B + I, g + D, I, D); return !0;
++      case 9627: this.ctx.fillRect(B, g, E, D); this.ctx.fillRect(B, g + D, I, D); return !0;
++      case 9628: this.ctx.fillRect(B, g, E, D); this.ctx.fillRect(B + I, g + D, I, D); return !0;
++      case 9629: this.ctx.fillRect(B + I, g, I, D); return !0;
++      case 9630: this.ctx.fillRect(B + I, g, I, D); this.ctx.fillRect(B, g + D, I, D); return !0;
++      case 9631: this.ctx.fillRect(B + I, g, I, C); this.ctx.fillRect(B, g + D, I, D); return !0;
++      default: return !1;
++    }
++  }
+@@ -1780,1 +1815,1 @@
 -        if (a && a.codepoint !== 0) {
 +        if (a && a.codepoint !== 0 && a.codepoint <= 1114111 && !(a.codepoint >= 55296 && a.codepoint <= 57343)) {
-@@ -2054,1 +2054,1 @@
+@@ -2054,1 +2089,1 @@
 -      if (!D || D.codepoint === 0)
 +      if (!D || D.codepoint === 0 || D.codepoint > 1114111 || D.codepoint >= 55296 && D.codepoint <= 57343)
-@@ -2205,1 +2205,2 @@
+@@ -2205,1 +2240,2 @@
 -      fontFamily: A.fontFamily ?? "monospace",
 +      fontFamily: A.fontFamily ?? "monospace",
 +      lineHeight: A.lineHeight ?? 1,
-@@ -2340,1 +2341,2 @@
+@@ -2340,1 +2376,2 @@
 -        fontFamily: this.options.fontFamily,
 +        fontFamily: this.options.fontFamily,
 +        lineHeight: this.options.lineHeight,