feat(#2014): hivectl open verb + Urls host request for web surfaces

docs/tools/hivectl-cli.md

@@ -36,6 +36,7 @@ This document contains the help content for the `hivectl` command-line program.
 * [`hivectl quota limit`↴](#hivectl-quota-limit)
 * [`hivectl subvol`↴](#hivectl-subvol)
 * [`hivectl subvol upgrade`↴](#hivectl-subvol-upgrade)
+* [`hivectl open`↴](#hivectl-open)
 * [`hivectl completions`↴](#hivectl-completions)
 
 ## `hivectl`
@@ -58,6 +59,7 @@ Sibling to the `hive-c0re` daemon binary. Covers host-side admin operations that
 * `restart` — Restart containers hive-wide — `stop` then `start` over the same scope. Bare `hivectl restart` restarts **everything** (all sub-agents plus the ci/forge/gateway/matrix infra containers); the same scope flags as `stop`/`start` narrow it (`--agents`, `--ci`, `--forge`, `--gateway`, `--matrix`, `--agent <name>`). If the stop phase reports a failure the start phase is skipped so the operator can investigate. Requires the hive-c0re daemon
 * `quota` — Per-agent disk accounting + optional quotas via btrfs qgroups
 * `subvol` — btrfs subvolume management for agent state dirs
+* `open` — Print (and best-effort open in a browser) a hive web surface URL
 * `completions` — Generate a shell completion script for `hivectl` and print it to stdout
 
 ###### **Options:**
@@ -527,6 +529,31 @@ Convert an existing plain-dir agent state root into a btrfs subvolume in place.
 
 
 
+## `hivectl open`
+
+Print (and best-effort open in a browser) a hive web surface URL.
+
+Resolves the URL from the running daemon (`HostRequest::Urls`), so custom forge / matrix domains work without guessing `forge.<domain>`. Prints the URL unconditionally — the reliable core, since the host is usually headless / driven over SSH where `xdg-open` is a no-op — then tries `xdg-open` as a convenience. Bare `hivectl open` opens the operator dashboard.
+
+**Usage:** `hivectl open [TARGET]`
+
+###### **Arguments:**
+
+* `<TARGET>` — Which surface to open. Defaults to the operator dashboard
+
+  Default value: `home`
+
+  Possible values:
+  - `home`:
+    The operator dashboard (`https://<domain>/`)
+  - `forge`:
+    The forge (Forgejo) web UI
+  - `matrix`:
+    The matrix GUI (fluffychat)
+
+
+
+
 ## `hivectl completions`
 
 Generate a shell completion script for `hivectl` and print it to stdout.