fix(#888): use gateway forge URL in dashboard links

Dashboard links to the forge were hardcoded as http://<hostname>:3000,
which breaks when the operator accesses the dashboard through
hive-gateway (forge is served at forge.<domain> with no port).

- nix/modules/hive-c0re.nix: inject HIVE_FORGE_PUBLIC_URL when
  forge.behindGateway = true (e.g. http://forge.pr1ma.darkest.space)
- hive-c0re/src/dashboard.rs: expose forge_url: Option<String> in
  StateSnapshot, reading from HIVE_FORGE_PUBLIC_URL
- frontend/packages/dashboard/src/tabs.js: use state.forge_url when
  present; fall back to http://<hostname>:3000 for gateway-off /
  local-dev deploys

frontend/packages/agent/src/app.js

@@ -1063,7 +1063,9 @@ window.marked = marked;
       const metaLinks = $('meta-links');
       if (metaLinks && Array.isArray(s.links)) {
         metaLinks.replaceChildren();
-        const forgeBase = `http://${window.location.hostname}:3000`;
+        // Prefer forge_public_url from state (set when the gateway serves
+        // forge at its sub-domain); fall back to :3000 for local-dev.
+        const forgeBase = s.forge_public_url || `http://${window.location.hostname}:3000`;
         s.links.forEach((lnk, i) => {
           const href = lnk.kind === 'forge'    ? forgeBase + (lnk.url || '')
                      : lnk.kind === 'external' ? (lnk.url || '')

frontend/packages/dashboard/src/tabs.js

@@ -580,7 +580,11 @@ window.marked = marked;
       // and must never reach the HTML parser.
       const navStrip = el('span', { class: 'nav-strip' });
       head.append(navStrip);
-      const forgeBase = `http://${hostname}:3000`;
+      // Forge public URL: prefer state.forge_public_url (set by the NixOS
+      // module when forge.behindGateway=true, e.g.
+      // "https://forge.pr1ma.darkest.space"), fall back to
+      // "<hostname>:3000" for gateway-off / local-dev deploys.
+      const forgeBase = (s && s.forge_public_url) || `http://${hostname}:3000`;
       // Container nav-strip links resolve against the same base as the
       // primary `name` link — gateway-prefixed when the gateway is in
       // front, direct TCP otherwise. Strips the trailing slash so
@@ -1786,7 +1790,11 @@ window.marked = marked;
     // forge link base — only when the hive-forge container is up.
     const fs = window.__hyperhive_state;
     const hostname = (fs && fs.hostname) || window.location.hostname;
-    const forgeBase = (fs && fs.forge_present) ? `http://${hostname}:3000` : null;
+    // Prefer state.forge_public_url (set when forge.behindGateway=true,
+    // e.g. "https://forge.pr1ma.darkest.space") over the direct :3000 port.
+    const forgeBase = (fs && fs.forge_present)
+      ? (fs.forge_public_url || `http://${hostname}:3000`)
+      : null;
 
     const ul = el('ul', { class: 'approvals' });
     for (const a of pending) {

hive-ag3nt/src/web_ui.rs

@@ -436,6 +436,12 @@ struct StateSnapshot {
     /// this directly. See [`docs/web-ui/dashboard.md::Container row`] for the
     /// frontend resolver + which links appear in which conditions.
     links: Vec<AgentLink>,
+    /// Public URL of the forge served by hive-gateway (e.g.
+    /// `"https://forge.pr1ma.darkest.space"`). Sourced from
+    /// `HIVE_FORGE_PUBLIC_URL`; `None` when `forge.behindGateway=false`
+    /// or the env var is absent. The frontend uses this to build forge
+    /// nav-strip links instead of hardcoding `<hostname>:3000`.
+    forge_public_url: Option<String>,
     /// Human name of this hive instance (e.g. `"pr1ma"`). Sourced
     /// from `HYPERHIVE_HIVE_NAME`; `None` when unset. The frontend
     /// uses this for the page `<title>` and header label so browser
@@ -585,6 +591,7 @@ async fn api_state(State(state): State<AppState>) -> axum::Json<StateSnapshot> {
         ctx_usage,
         cost_usage,
         links: agent_links(&state.label, state.gui_vnc_port.is_some()),
+        forge_public_url: std::env::var("HIVE_FORGE_PUBLIC_URL").ok().filter(|s| !s.is_empty()),
         hive_name: crate::identity::hive_name(),
         swarm_name: crate::identity::swarm_name(),
     })

hive-c0re/src/dashboard.rs

@@ -250,6 +250,12 @@ struct StateSnapshot {
     /// local-dev deploys keep working. See `docs/gateway.md::Vhost
     /// map`.
     gateway_enabled: bool,
+    /// Public URL of the forge vhost served by hive-gateway (e.g.
+    /// `"http://forge.pr1ma.darkest.space"`). Sourced from the
+    /// `HIVE_FORGE_PUBLIC_URL` env var, which the c0re NixOS module
+    /// sets when `forge.behindGateway = true`. `None` when absent —
+    /// the frontend falls back to `http://<hostname>:3000`.
+    forge_public_url: Option<String>,
     /// Human name of this single-host hive instance (e.g. `"pr1ma"`).
     /// Sourced from `HYPERHIVE_HIVE_NAME` env var, set by the c0re
     /// NixOS module from `services.hyperhive.hiveName`. `None` when
@@ -466,6 +472,7 @@ async fn api_state(headers: HeaderMap, State(state): State<AppState>) -> axum::J
             let s = v.to_string_lossy().to_ascii_lowercase();
             matches!(s.as_str(), "1" | "true" | "yes")
         }),
+        forge_public_url: std::env::var("HIVE_FORGE_PUBLIC_URL").ok().filter(|s| !s.is_empty()),
         hive_name: std::env::var("HYPERHIVE_HIVE_NAME").ok().filter(|s| !s.is_empty()),
         swarm_name: std::env::var("HYPERHIVE_SWARM_NAME").ok().filter(|s| !s.is_empty()),
     })

nix/modules/hive-c0re.nix

@@ -299,6 +299,16 @@ in
         # When true the dashboard builds same-origin `/agent/<name>/`
         # links; when false it falls back to direct `<host>:<port>` TCP.
         HIVE_GATEWAY_ENABLED = "1";
+      }
+      // lib.optionalAttrs (config.services.hyperhive.forge.enable && config.services.hyperhive.forge.behindGateway) {
+        # Public URL of the forge vhost served by hive-gateway. The
+        # dashboard uses this to build browser-facing forge links
+        # instead of hardcoding `<hostname>:3000`, which breaks when
+        # the operator accesses the dashboard through the gateway
+        # (forge sub-domain has no port; direct port URL would be
+        # wrong). Absent when `behindGateway = false` — dashboard
+        # falls back to `<hostname>:3000`.
+        HIVE_FORGE_PUBLIC_URL = "https://${config.services.hyperhive.forge.domain}";
       };
       serviceConfig = {
         ExecStart = "${cfg.package}/bin/hive-c0re --socket /run/hyperhive/host.sock serve --hyperhive-flake ${cfg.hyperhiveFlake} --dashboard-port ${toString cfg.dashboardPort} --operator-pronouns ${lib.escapeShellArg cfg.operatorPronouns} --context-window-tokens ${lib.escapeShellArg (builtins.toJSON cfg.contextWindowTokens)}";