Architecture: prevent overflow, tighten columns

Root cause of the frame-breaking 'zoom' look: uppercase headings with
large letter-spacing inside minmax(0,1fr) grid cells pushed min-content
past the cell edge and bled outside the diagram frame.

Fixes:
- min-width: 0 on every arch-grid descendant so cells can actually
  shrink to their allocated width
- overflow: hidden on the outer diagram and on inner dia-box so any
  residual overflow is clipped to the frame
- Shrink letter-spacing in arch h5 (0.12em -> 0.06em) and add
  overflow-wrap: anywhere so long tokens wrap instead of forcing
  width
- Tighten fixed columns: 150/72/280 -> 140/64/260
- Let bridge-row labels wrap (drop white-space: nowrap)

Author: Codegass

website/css/style.css

@@ -727,17 +727,31 @@ header.g {
 .arch-overview .diagram,
 .diagram.arch-overview {
   padding: 16px;
+  max-width: 100%;
+  overflow: hidden;
 }
 
 .arch-grid {
   display: grid;
-  grid-template-columns: 150px minmax(0, 1fr) 72px 280px;
+  grid-template-columns: 140px minmax(0, 1fr) 64px 260px;
   grid-template-rows: auto auto;
   grid-template-areas:
     "input  react   bridge  docker"
     "report valid   bridge  docker";
   gap: 10px;
   align-items: stretch;
+  max-width: 100%;
+  min-width: 0;
+}
+
+/* Prevent any arch-grid child from pushing min-content past its cell */
+.arch-grid > * { min-width: 0; }
+.arch-grid .dia-box,
+.arch-grid .dia-section,
+.arch-grid .react-quad,
+.arch-grid .v-grid,
+.arch-grid .ag-fs-inner {
+  min-width: 0;
 }
 
 .ag-input  { grid-area: input;  }
@@ -780,14 +794,24 @@ header.g {
 /* Compact dia-box inside arch grid — smaller padding, smaller list gaps */
 .arch-grid .dia-box {
   padding: 8px 10px;
+  overflow: hidden;
 }
 .arch-grid .dia-box h5 {
   font-size: 0.5rem;
+  letter-spacing: 0.06em;
   margin-bottom: 4px;
+  overflow-wrap: anywhere;
+  word-break: break-word;
 }
 .arch-grid .dia-box ul {
   font-size: 0.625rem;
   line-height: 1.55;
+  overflow-wrap: anywhere;
+}
+
+.arch-grid .ag-section-header {
+  letter-spacing: 0.08em;
+  overflow-wrap: anywhere;
 }
 
 /* ReAct internal quad: 2 rows × (box arrow box) */
@@ -885,10 +909,11 @@ header.g {
 .ag-bridge-row .lbl {
   font-family: var(--mono);
   font-size: 0.5rem;
-  letter-spacing: 0.08em;
+  letter-spacing: 0.06em;
   text-transform: uppercase;
   color: var(--fg-faint);
-  white-space: nowrap;
+  text-align: center;
+  line-height: 1.3;
 }
 
 /* Validator target label */